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Engine Specific Info and Questions => IDI Engine => Topic started by: Jetmugg on June 09, 2014, 01:39:03 pm
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After watching my Ohio Mile runs a little closer, I have noticed a scary sight. :o
My oil pressure gauge shows that I'm having some momentary drops in oil pressure at higher rpm's. I wonder if I'm foaming the oil?
While I'm driving it, I'm too busy looking out the front window, but the video shows some loss of pressure (first gauge to the right of the steering wheel). Scary.
https://www.youtube.com/watch?v=PBGNUAL5nzw&feature=youtu.be
Steve.
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Wow - yeah that doesn't look good...
Fortunately a ready made easy to install windage tray solution exists (if that is indeed what the problem is)
https://www.greaseworks.com/store/index.php?route=product/product&product_id=341
I used one on my AHU build...
I assume your timing belt is tight enough - if it is loose or if there are any oil leaks around it the belt can slip on the IM shaft pulley fairly easily. Seems like it is only happening at the top of your RPM range. Really though the belt is being pulled hard against that pulley by the engine so it SHOULDN'T be a problem...
Are you allowed to use a custom oil pan? Something with a couple quarts more capacity definitely wouldn't hurt and would help mitigate foaming - just some side chambers welded to a stock pan would be dandy.
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I will check the belt tension for sure. My mind is racing, trying to figure out how I can have a loss of OP at higher rpm's.
The video shows a "bobble" of oil pressure in 3rd gear as well, but it comes right back.
I can use any pan I want, but there's not a lot of ground clearance underneath this thing.
I'm hoping to see some skid marks on the belt that may indicate some slippage.
Oil foaming at higher rpm's is the only other thing that comes to mind right away.
Steve.
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Those are the exact gauges I have IIRC the autometer sport comp 2". If you are running an electric like mine and not a manual gauge then I bet you have a ground issue or a loose wire. 4th looked scary, but for you to lose pressure like you did in 3rd the truck should have blown up if it was for real. Usually you don't lose it all at once like you did in 3rd. 4th looked more gradual and believable. Check the wiring or wiggle it and see if you get any results.
You did use the little plastic thing that clips onto the pickup tube didn't you? I honestly think that is all you would need. I use the windage tray, but I don't think it helps with the oil pressure as much as wind up.
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The first 1.6td jetta I got had low oil pressure down low at idle and it was dipping just a bit below spec at speed. That annoying buzzer system I thought was freaking out was warning me I guess.
That engine was tired with blowby and flaked im bearings but I let family run that sucker for years until the head gasket blew after a blown coolant hose.
There is this 18 mile stretch of twisty up/down mountain that we had to try and drive like a race car to get around people and get to work in a reasonable amount of time and that car would get pissed with the buzzer on the sudden turns and long sweepers.
I have had other use engines since that were borderline oil pressure spec with flaked im bearings but they didn't do what that first engine did.
I have since freshened up 3 daily drivers and used the cam cover, windage try with 36mm oil pump and the plastic deflector and I have never seen this crazy drop in oil pressure since. I use auber gages now.
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in 4th I could see a steady loss of pressure, I wouldn't rev the rpms up until you get this solved; nice run though,, belt could be slipping, could be a bad im shaft, bearings, or vac pump/oil pump drive could be adding drag to shaft/belt.
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I''m planning to move forward on at least 2 fronts....
First, my mind won't be able to stop thinking about possible causes. Windage/oil frothing seems to be the first thing that I'm thinking about. However, I can't explain everything I see in the video based only on that. In 3rd gear, the OP jumping around, losing it and then getting it back while accelerating, I can't quite figure that part out.
In 4th, the OP goes away at higher rpms (probably around 5K), but then comes right back as soon as I lift out of the throttle. There's another one I can't quite explain.
Over the next few days, I'll be carefully draining and inspecting the oil, along with cutting the filter apart and looking for any debris.
I was using Mobil 1 Turbodiesel Truck oil (5w30), and a Bosch oil filter.
I will most likely pull the oil pan as well, at which time I can pull a main cap and a rod cap for bearing inspection.
This engine is very fresh (probably less than 20 miles on it), and was broken in on a chassis dyno, using Joe Gibbs break-in oil.
The IM shaft bearings were replaced at the rebuild.
The belt might be a tiny bit loose, but I don't think it can explain what is seen in the video. I will snug it up.
There are no leaks.
When I put the bottom end back together, it will get a windage tray.
I'll also have a look at modifying an extra oil pan to give additional capacity, and a more protected area for the turbo drainback line to discharge.
I'll be moving the GoPro camera more forward and centered up, to give a better view of the gauges for future runs.
Keeping my fingers crossed.
Steve.
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Well i have few ideas....
Oil too thin... Gets too hot by that point.... Whats oil temp?
Oil pressure releife valves do goofy things....
Aaz head has hydro valves.... Starting to float giving issue...
But first to me... Wrong oil for application.... If its got hydro valves, had to use oil pump for hydro... The vac pump could also be seizing up... Belt slips... No op...
For your egt, for mile... Turbo red hot.... At min 15w40... Id do 20w 50 for salt flats... Turns to piss water thru turbo, dummps head op where gaugemounted
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The vac pump is gutted, so I don't think there's an issue there, but I will pull the cap just to be sure.
I'm definitely considering heavier oil - didn't realize there was a different spec for hydraulic engines.
I'm using the 36mm oil pump.
The guage sending unit is mounted in the back of the head (over the transaxle).
I'm planning to add a great big red Oil Pressure warning light right next to the tach!
Keep the suggestions flowing, please. I need to regain piece of mind before Bonneville.
The engine didn't sound any different or stop pulling when the OP dropped. Thinking back, I might have expected some lifter problems.
Steve.
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I personally don't think the oil is a problem, mobil 1 syn is good for most applications. I d think of checking end of im shaft, the end-play that collar is rather thin, but you have to remove timing belt to get at it. 1 thing I was thinking over prolonged high rpm, there may not be enough oil in pan, shouldn't be a problem, but the oil level may at these high rpms be going lower than the pump intake. oil foaming with this oil may be a problem, its pretty good oil, but with these high prolonged rpms its possible. ?try a stronger oil?
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I used to mess around with Oldsmobile powered jet boats (455's). They were known for their propensity to pump all the oil out of the bottom of the pan. They couldn't drain the oil back to the pan fast enough to ensure proper oiling. I was wondering if there were any issues with VW hydraulic diesels in this respect. I'll check my "puke can" to see how much oil is in it, but I don't see how it's possible for the upper part of the engine to hold the entire 4 or 5 quarts of oil.
My gut says that windage problems are causing this, but I don't have a good way to check, other than adding a windage tray and making some more high speed runs.
I am running a Summit Racing oil filter/cooler adapter, and a pretty good sized oil cooler in front of the radiator. Oil temp doesn't look like a problem, but I will check the video and the gauge readings to verify.
My turbo oil drain-back is a braided -10 A/N line (5/8" inside diameter) that discharges directly into the oil pan through a bulkhead fitting. The fitting is located on the back side of the pan (towards the firewall), a couple of inches back from the crank pulley.
My sense is that if I had an IM bearing problem, the oil pressure would be low throughout the RPM range, and not manifest itself as a problem only in the upper RPMS.
As far as picking the right oil, I have 100% confidence in Mobil 1, and it's provided free of charge from one of my sponsors. That being said, there are enough different grades of Mobil 1 that it might be beneficial to spend some time checking other weights of oil.
Thanks for all the brainstorming, guys!
Steve.
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I really think you have a gauge issue, maybe not if you have the smaller 3 quart oil pan instead of the 4 quart like most have. I have a 4 quart I would send you for shipping if you need it. I have those exact gauges and they did similar to me a few times. FREAKED out and then went over connections and it hasn't happened again. I don't have hydro lifters but I do have a hydro head and 36mm oil pump.
The only other thought I have is maybe your oil cooler/lines could be suspect. I really have a hard time believing that it is foaming. If you have say 3/8" lines on your oil cooler at 5k rpm it may not flow enough to sustain pressure to the head like you want. The head loses pressure first since it is last to get the oil. Then when you let off you see it jump right up as the oil is there, just not enough to flow the pressure you want. If this is the case a thicker oil may yield worse results as it could find it harder to get through. IIRC I used 1/2" lines on my oil cooler, but if you have to change it I would research what is best.
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as far as I know and have seen there are no oil return issues with the vw engines. Same head design as the gassers that run even higher RPM with no issues. The hydro head has 4 very large oil return holes, so I doubt it is an issue.
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For racing here is the oil I would use if you get it free anyway. I like scheaffers oil myself, but free is free and Mobile makes ok stuff.
http://www.theoilhub.com/Mobil_1_15W50?src=Google&gclid=COD2kqO6774CFdSMMgodkXkAaQ
also, I know it is hard to do with your cooler full of ice, but I usually don't boost hard until the oil temp is 150f or higher. It doesn't flow correctly until then...stuff you are probably already doing, but figured I would share.
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15W-50 sounds good. I'm sure Mr. Bauman at Bauman Oil will be willing to provide a jug of the good stuff.
I will be changing my icewater cooler operation a bit. I'll warm the engine up without running the circulation pump, then will turn on the intercooler icewater pump just before the competition run.
Steve.
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https://www.mobiloil.com/USA-English/MotorOil/Oils/Mobil_1_Racing_0W-50.aspx
I just saw this too. It would be great if it is diesel rated, but even if not and you change it after every 3 or 4 passes the soot shouldn't be an issue.
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A 2-pronged approach might be to drop the pan and do the windage tray, plus add a mechanical oil pressure gauge running off the filter flange.
When troubleshooting it is good to keep the changes to a minimum or you'll never know what actually fixed the problem.
As far as oil weight is concerned I'd think you'd want the lightest weight oil that will stay together at the temps you are running. NASCAR for instance run 0W5 to minimize friction. It's not like this oil needs to live to 10,000 miles in stop and go driving, you can cook the hell out of it in a few runs and then dump and reload - you're getting it from a sponsor anyhow! Yes, a 15W50 will make more pressure, there's no denying that, but it's also going to be waaaay thicker meaning more drag on all your bearings and your oil pump.
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So how many of YOU Have screwed with 85 golf 1.8 hydro engines??
Telling you... Its a oil thickness issue for oil temp....
They had issues of wrong oil pumps in pa for hydro golf engines.... Seen it... Blew hours trying to resolve it till oil ppump of wrong size installes in westmorland... How i learned differance in such things...
Mr jetmug left u pm with my #... Feel free to call, text...
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I'll check the high-res version of the video and get back to you with the temp readings.
I only keeping my engine from kersploding.
Will send follow-up text.
Steve.
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Good news, I drained the oil, and it was clean (no visible metal particles).
I removed the filter and cut it apart (no visible metal particles).
I pulled the oil pan off and visually inspected the bottom end. Everything looks as it should.
I'm going to order a pan gasket/windage tray combo, fill it with heavier oil, and see what that does for me.
Steve.
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Good deal.
Do you have another dyno planned to test or how are you going to do it?
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I think the gauge wiring is suspect as theman mentioned. Possibly a flaky ground.
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I will run a separate, dedicated ground wire from the body of the sending unit directly to a main ground terminal in the cabin of the truck.
I'm also going to add a big, bright warning light in the event of oil pressure drop.
Althought 123 mph isn't nearly as fast as most LSR vehicles, there still isn't a lot of time to be scanning the gauges.
Steve.
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I think the gauge wiring is suspect as theman mentioned. Possibly a flaky ground.
If it isn't I am hoping it is just the film strength of the oil not being enough like CRSMP5 was saying. That turbo being cooled by the oil and running sustained EGT of over 1,000f the oil hydrodynamic film should be about done especially with 5w-30. It was in the 80's this weekend and I am sure it will be hotter in the salt desert which wouldn't help matters. I wouldn't want to run a street car across the salt flats at 55mph and reasonable rpms with 5w-30...maybe a newer car that is designed for 5-20 or something. I am glad he is going to run something thicker
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I'm back and forth mentally, but will probably step up to Mobil 1 15W-50, or a conventional 20W50.
Steve.
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Guys, I just posted the following in another thread.
Put a mechanical gauge on it, and check the oil pressure. If it's excessive it is sucking the pan dry. Also, windage does not come in to play at lower rpm's (typically under 6K rpm). A deep skirted block might nudge that down slightly, but our blocks are not deep skirted, nor are they capable of exceeding 6K rpms, so windage is not a factor. Nor would viscosity/oil effect oil pressure in the manner described in the OP. I offer the following and have disassembled the pumps to verify the source...
Guys, there seems to be a common thread when I start discussing oil leaks in these engines. I completely rebuilt my 82 1.6 about a year ago, and was not happy to see the recurring puddles under mine. However, the tendency for these engines to leak around the valve cover seals is routine - but it shouldn't be considered "normal". Here's why:
I build mostly hotrod and race engines (American Iron and a few diesels), so I decided to put an oil pressure gauge on my engine to check new pumps oil pressure. It was in the stratosphere at 80 to 100 lbs while cruising at freeway speed. My truck has the .75 5th gear and the rpm's are under 4K @ 70 mph. The oil pressure requirement on a full-fledged race engine is 10 pounds per 1000 rpm - stock engines is ~6 psi/1K rpm; meaning our engines should never exceed 40-50 pounds oil pressure. My Cummins dually rarely exceeds 45 pounds and leaks and oil pressure are not a problem - even after 250K miles...
I built a blown hemi years ago for a pro-street car, and installed a customers Keith Black "top fuel" pump as he had requested. In less than 5 minutes it would suck the oil pan completely dry and register zero oil pressure !!! Extreme oil pressure can destroy an engine. Obviously, the VW diesel is at the other end of the extreme, but high oil pressure WILL cause leaks in ANY engine. Exceed more than 10 lbs/1K rpms and you're running higher pressure than most RACE engines. .Think about it
I decided to dig in a little deeper, and I've got some photos I can post if anyone wants to see why our engines run excessive oil pressure - excess pressure that pushes too much oil to the upper end, flooding the cylinder head, resulting in leaks. Maybe it's a pure coincidence that the valve cover gaskets and seals are the most poorly designed gaskets on these engines.
I've commented on excessively high oil pressures in the past, and I'm pretty sure someone else has posted about this, so I took a used oil pump apart I had lying around; drilled out the spring retainer plate; and removed the spring and bypass piston, cover and gears.
Turns out the clearance between the bypass piston and bore in the oil pump is so tight, that even the smallest of debris causes the bypass piston to lock up. I had to force its removal, and both piston and bore were significantly scored.
I'm planning to pull the pan and pump on my trick in the next few weeks and I'm going to ream the piston bore to give another .002 clearance. I'm also going to check spring rate, and order a lighter spring to get this thing down to ~40 psi max at cruise speed.
I'll keep you guys posted, but I'd be willing to bet most of our oil leaks would be eliminated, or at least significantly reduced, if we can just get the oil pressures down to reasonable levels (10 psi @ idle and <50 lbs cruising - hot).
Southernman
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The only external oil leak caused by excessive pressure is somewhere north of 250 PSI, the filter either rips apart, or pulls off its threads.
Insufficient drainback may be a possibility.
The real challenge of our oil leakage is the positive pressure crankcase ventilation system making every seal want to leak.
How are these motors not able to exceed 6000 RPM?
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I spun mine over 6K on multiple occasions at The Ohio Mile. ;D
Not by much, but for sure over 6K. Dieselmeken AB build the pump to work at those RPM's.
I am a bit concerned about the location of the oil drainback from my turbo. It is plumbed through the back of the oil pan through a bulkhead fitting. I need to check the exact location of the bulkhead fitting with respect to the crank. I just want some piece of mind that the flow of the return line isn't somehow contributing to windage or frothing.
With respect to a mechanical gauge, I am not planning to install one due to the regulations associated with Land Speed Racing. It could not be plumbed directly from the engine to the dash, and I'm not looking to add more complexity in the form of an isolator and more external plumbing.
I am planning to install a secondary Oil Pressure warning light in the form of a large and bright "shift light" indicator next to the tach.
I did order a windage tray/OP gasket. I also have the opportunity to run on a chassis dyno again before Bonneville. That will provide some peace of mind.
Steve
Steve.
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The good news is that there are NO external leaks on my engine. No valve cover leaks, no IM shaft leaks, no pan leaks. No leaks. Hooray.
I am running a 36 mm "turbo" oil pump, since the block is plumbed with oil squirters. It's a hydraulic lifter engine as well. If the OP loss continues to be an issue, I can (and will) swap in one of the smaller oil pumps as a trial (I've forgotten the mm size of the non-turbo oil pumps).
Steve.
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Southernman - do you have a link to the other thread you were posting in?
Steve.
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Jetmugg, congrats on your no leak engine!
I wish I could say the same and I'm not even running on the salt. May I ask what type/brand/part number of sealant you used and where? Also, were there any "procedures' you did that were part of your success? I know spotlessly clean is required.
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Since this was a complete rebuild, all of the surfaces were squeaky clean, which definitely helped. I made sure all the drilled and tapped holes were clean and that fasteners threaded in smoothly before final assembly. Any holes that needed to be chased out were chased with a bottom tap.
I used the regular Victor Reinz gasket set and the aerosol type Hylomar on all gaskets. I would hang each gasket from a short piece of utility wire, and then spray a couple of light coats of Hylomar on each side of the gasket before assembly.
The only place I used any RTV was on the ends of the cam tower caps, and I used it very sparingly. It's an AAZ head on a 1.6 Turbo block.
My breather setup is also non-stock. I welded an AN bung fitting in place of the rubber grommet on the valve cover, and it's plumbed directly to a Moroso "puke can" with a filtered and vented lid.
Steve.
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I am running a 36 mm "turbo" oil pump, since the block is plumbed with oil squirters. It's a hydraulic lifter engine as well. If the OP loss continues to be an issue, I can (and will) swap in one of the smaller oil pumps as a trial (I've forgotten the mm size of the non-turbo oil pumps).
I don't think your 'trial' with a smaller oil pump can give any good results. you want a 36mm pump, and you have hydro lifters too. they require 36mm.
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I suppose if it is pumping all of the oil out of the pan, overfilling may be an option. I certainly wouldn't want to overfill unless I was sure the windage tray was keeping the oil away from the crank, though.
So many possibilities...
Steve.
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For the sake of accurate info, it wasn't until midway through the run of hydro 1.6TD engines that VW went from 30mm to 36mm oil pumps. There were 2 or 3 years of hydro 1.6TD engines that came with 30mm oil pumps.
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Thanks, Libby. I'd be interested to hear any of your thoughts on this situation. I realize that the GoPro video I posted isn't very High-Def, but the oil pressure changes are visible (OP is the first gauge to the right of the steering wheel).
https://www.youtube.com/watch?v=PBGNUAL5nzw
Steve.
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As soon as I lift off the throttle (after passing through the 1 mile timing lights), the oil pressure jumps right back up.
Steve.
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First I would confirm gauge operation by installing a mechanical OP gauge. I have had several electronic gauge senders fail with few miles on them. I odn't think they like the diesel vibrations. On several TD engines in vanagons I have observed that when the oil level is even slightly low, then OP drops as boost rises much like what your video shows. I have always assumed it was due to aeration. If that is your issue, the simple solution is to add more oil. A larger oil pan and a lower oil pickup tube would help as well.
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my idea wasn't adding oil, but lengthening the pick-up tube, as its not even 2 qts that are going to be out and around engine, draining back, etc. the pick-up tube may only go down into the oil pan 1.5qts maybe less. you wont have as much as 3 whole qts out of the oil pan, I don't figure. lengthening the pick-up tube will guarantee your not sucking down your oil level because your runs are at prolonged hi-revs, and you don't have to add extra oil, but the effect is similar.
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OK - I can come up with a mechanical gauge for some testing.
Since the pan is off the engine now, I can also do some measuring to determine how much clearance there is between the bottom of the pick-up and the inside of the pan.
I'm trying to give consideration to all possibilities. I can do all kinds of testing here, in order to ensure the greatest chance of success at Bonneville.
Steve.
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The other pumps are 26 and 30mm gears. The pressure is the same for the spring is the same, but it is supposed to move more volume of oil with the larger gears.
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Yeah - I have always assumed that the larger gears actually create more oil flow, not necessarily more pressure. Any increase in pressure comes from a restriction in the flow somewhere "downstream" in the system.
Looking through the Bentley, I also noticed that early engines call for almost 1 quart less oil than later models. Were there different dipsticks on early vs late diesel engines?
I have no idea what engine the dipstick I'm using came from.
Steve.
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I didn't notice a change with 36mm in pump on 2 turbo blocks as far as oil pressure. I just assumed it was "better" to have the bigger ones so I put them on my daily drivers.
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Yeah - I have always assumed that the larger gears actually create more oil flow, not necessarily more pressure. Any increase in pressure comes from a restriction in the flow somewhere "downstream" in the system.
Looking through the Bentley, I also noticed that early engines call for almost 1 quart less oil than later models. Were there different dipsticks on early vs late diesel engines?
I have no idea what engine the dipstick I'm using came from.
Steve.
IIRC the dipstick should be fine if the dipstick tube and dipstick are correct for each other. The early 1.6 gassers and I think the early 1.5 diesels had a 3 qt pan. That is why I asked you earlier if you needed a 4 qt. pan. The later vw 8v engines all had the 4qt pan...making it a 5 qt oil change with the filter. The early pan you could only do around 4 qt oil change with the filter and that smaller pan.
One interesting thing I found with my 1.6 vs the 1.9 aaz engines I have is that the IM shafts drive pulley is considerably smaller on the aaz vs the 1.6.
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One interesting thing I found with my 1.6 vs the 1.9 aaz engines I have is that the IM shafts drive pulley is considerably smaller on the aaz vs the 1.6.
making the im shaft speed greater, possibly to speed up oil pump.
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One interesting thing I found with my 1.6 vs the 1.9 aaz engines I have is that the IM shafts drive pulley is considerably smaller on the aaz vs the 1.6.
making the im shaft speed greater, possibly to speed up oil pump.
Yes, but would the pulleys interchange? The IM shafts are different IIRC.
Also to chime in on the oil pump flow/pressure thing, the main reason higher volume oil pumps are installed is to be able to maintain a higher oil pressure at higher oil temperatures, and do it for longer in the engine's service life. Couple that with modifications (A turbo and piston cooling jets to feed, an oil cooler creating more volume in your pressurized oil circuit) and a higher-volume oil pump becomes not only a good idea but sometimes a necessity on higher power applications/ Don't forget that some components like the turbo use oil as a cooling medium, so the more oil flowing through them the better. This could all be simulated by increasing pump speed by swapping on an AAZ IC pulley, if it can be swapped, but the only question i'd have for an already used engine is would it increase both oil and vacuum pump wear (the IC drives the vac pump too, don't forget).
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[/quote]
IIRC the dipstick should be fine if the dipstick tube and dipstick are correct for each other. The early 1.6 gassers and I think the early 1.5 diesels had a 3 qt pan. That is why I asked you earlier if you needed a 4 qt. pan. The later vw 8v engines all had the 4qt pan...making it a 5 qt oil change with the filter. The early pan you could only do around 4 qt oil change with the filter and that smaller pan.
One interesting thing I found with my 1.6 vs the 1.9 aaz engines I have is that the IM shafts drive pulley is considerably smaller on the aaz vs the 1.6.
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OK - it's time for me to learn about the differences in the various oil pans, and how to ID them. I have at least 2 pans that I could use. I'll do some measuring and inspecting to try to figure out if they are different from one another. Are the oil pump pickup tubes the same for the 3qt and the 4 qt pans in terms of "depth"? I'm hoping that the larger pan isn't any deeper, but maybe has some other dimensions modified to give the extra volume.
Regarding the AAZ pulley, the IM shaft would definitely be sped up. I don't think I need that. IIRC, the timing belts are the same on a 1.6 and a 1.9. The smaller pulley has to play a part in allowing the same belt to be used for either application. Since the 1.9 has the taller block, it would need the smaller pulley.
Steve.
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If the issue is aeration and your turbo return is already coming from above the oil level, then you either need increase the oil level so the bubbles are higher, draw from lower in the pan if that is possible or created some added baffling so that the bubbles separate from the oil you are pulling into the oil pump. You really don't want any aerated oil entering the oil pump. You want the bubbles to rise out of the oil before it is drawn into the pickup tube. Increasing the capacity by changing the pan and yet keeping the oil level and the level of the pickup tube the same may reduce the issue some but will not eliminate it. I'd shoot for eliminating it.
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All options are on the table. I have another pan I could modify, and I am willing to buy a different pan if necessary, although I'd prefer not to spend $500 on a pan.
Steve.
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Steve, you can simply click on my avatar to get to my profile/postings, and thanks for responding.
I doubt the bulkhead fitting is affecting your oil pressures - unless the lines and fitting are under sized and inhibiting return to the pan. Such condition would result in the same "pooling" in the upper end I described above, and the turbo seals would probably be leaking some...
Also, my post wasn't about whether or not our engines 'can' work above 6K. I'm sure some do, but doing so with cast pistons, and stock rods, under boost, in excess of 500 lbs cylinder pressure, guarantees we won't do it for long... My discussion was focused on 'optimal' pressures. Unless you're running alt fuels (like Nitro methane where cylinder pressures can destroy parts even at idle), anything beyond 10 psi/1K rpm is excessive.
The 'turbo' pumps, used in conjunction with the hydraulic lifter are indeed based on volume - not pressure. The additive volume based on turbo's consumption, 16 'hollow' lifters, and squirters to keep pistons alive, require additional 'volume - not pressure'. The turbos I've ran over the years always used restrictors to limit both... However, matching a turbo/hydraulic pump should not result in additional pressure.
Excessive oil pressure in any engine is counterproductive, not to mention a drain on horsepower, and economy, as rpm's, and viscosity, increase...
Regarding the mechanical gauge; temporarily install it where the existing sender is threaded and fish the poly tubing to a gauge long enough to check it. The ONLY way your pressure will drop, is due to the oil level in the pan dropping below the pick up - assuming the engine you're running meets, minimal, factory blueprint/specs... If that's not the case, then loss of 'restriction' due to excessive clearances will cause a drop in pressure, but it's usually constant, not intermittent.
I hope this helps...
Just for reference guys, here's my latest project: a 528 cu. in Mopar Wedge sporting a Precision ceramic 106mm turbo. Estimated 1200-1500 Hp and setting it up to run Yellowbullet's door slammer division. Should be good or 8 second quarter mile times...
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The ONLY way your pressure will drop, is due to the oil level in the pan dropping below the pick up - assuming the engine you're running meets, minimal, factory blueprint/specs...
Aeration of the oil can occur without the oil level dropping below the pickup and drawing in aerated oil will cause the oil pressure to drop in direct proportion to the amount of air bubbles in the oil. I have observed several VW TD engines (both higher mileage and completely rebuilt with every oil clearance well within spec) that would drop oil pressure in direct relation to boost. I have observed the oil pressure drop 30+ psi without the rpms changing. The only explanation I have for that behavior is aeration of the oil. It can be seen in the design of the baffles in the 1.6TD vanagon pan that the VW engineers were aware of this issue.
The typical solution is to have the return oil from the turbo enter above the oil level. This typically works well enough, but I can see where an engine running high rpms and high boost would be circulating the oil in the sump faster than the bubbles could rise out of it.
To address aeration, I would add a semicircle to the perimeter of the pan that had a gap at the bottom (say 1/4"), with the top of the enclosure extending a little way above the oil level. The semicircle would contain the oil return fitting and would catch all of the aerated oil from the turbo. The bubbles would float and stay inside the enclosure and the non-aerated oil would return to the main portion of the pan through the gap at the bottom of the 'fence'. I would add a second similar baffle around the oil pickup. I would use the large capacity oil pan. I would also measure to see if the oil pickup could be lowered closer to the bottom of the pan. I would also add the windage tray and experiment with raising the oil level.
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Libby, thanks for responding.
Doesn't change the solution since uncovering the pump inlet is behind the loss in pressure in either scenario...
In essence, your take here is frothing of the oil creates a condition where there is inadequate time for air saturated oil to return to the pan in a fully liquid state. Air has displaced liquid; the pump starves; and the OP gauge responds accordingly. You may be right, and the most simple test here is to cut the engine and stop the vehicle, after a max rpm blast, and pull the dipstick...
Option 1, you're either pursuing a dry-sump solution, which is designed to control such conditions - or Option 2, you're dropping the oil sump and pickup and increasing the volume to buy time for the oil to eject entrained air.
Option 1 is the bucks up solution, and probably requires homebuilt engineering for the 1.6, but could be done.
Again, thanks for the reply,
Southernman
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There is at least 1 dry sump solution commercially available. I have talked to them, and it's definitely a "bucks up" solution that I don't think I'd be able to pull together before Bonneville (although it would be very nice).
Optimizing the "stock" setup is more realistic. I'm headed out to the garage right now, attempting to figure out some oil levels, volumes, and position of my current oil return line from the turbo. I think it's above the static oil level, but will check to be sure.
Pan baffling is certainly do-able.
The key is that it has to work for more than a 1/4 mile blast. It essentially has to work "steady state", as even the short course at Bonneville is 3 miles WFO.
Steve.
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OK - another update. ;D
I do have one of the deeper pans "in stock" in my garage. I believe it's actually from a code 9A 2.0 gas engine that I bought last year. It is somewhere around 5/8" deeper than the other 2 pans I have, including the one that was on the engine.
I will be using the 9A pan. It needs to have a weld bung installed for the oil return from the turbo. What are the thoughts on the bung location? As high as possible on the pan, or down towards the bottom?
Also, this is the oil pump and pickup tube that's currently on the engine:
http://www.partsplaceinc.com/products/product-detail.aspx?keyword=VW+Diesel+Oil+Pump68-115-105&sku=1300
Measuring from the bottom skirt of the block to the bottom of the pickup tube, it's showing about 3-1/2". For comparison, I measured another 1.6D engine I have laying around (with no oil pan). The OEM pickup appears to be about 4" down from the skirt. So right away, I'm giving away 1/2" of oil that can't get picked up.
When I go to the deeper pan, that dimension (from the bottom of the pickup tube to the bottom of the inside of the pan) will be over 1"!!!
I need to either come up with a different pickup tube, or weld some tubing into the one I already have.
Back to the garage for now.
Steve.
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Keep tho oil return bung as high as you can. Drop the pickup as low as you can. Keep the 36mm pump. If you are thinking of swapping oil pickup tubes, be sure to swap just the tube and not the bottom plate of the pump as that houses the pressure relief valve which is matched to the pump. I'd still add baffles to prevent aerated oil from getting to the pickup.
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Sounds like a plan! ;D
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I am hoping that is the issue, you were just running low on oil to pump. I second what Libbydiesel says to keep the oil bung as high as possible. While welding mine in I found that you need to keep it cool. I warped the pan where the gasket seals and there was always a little leak there. Tig would be your friend on that one. I kept mine about 1" from the top of the pan as I needed to be able to get a wrench on my fitting on the drain line.
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Steve, there are a few other thing that you may want to consider:
In my decades as an engine builder (mostly V-8's, naturally aspirated; supercharged; and turbo-charged) centrifugal force plays a huge role in 'where' oil resides inside your engine.
For example, any V-8 engine that is revved to 6K and beyond can hold at least 4 quarts of oil on the crankshaft alone. That's also how most race builders came up with deep pans of 8 quart capacity (with 4 qts clinging to the crank, and 5 available for everything else once you include filter capacity). Where crank scrapers are employed, the pan volume can be reduced by 1-2 quarts, hence the 'compromise' pans at 7 quarts, which also help keep the sump out of the path of speed bumps for those inclined to drive such on the street.
My recommendation, based on the information above, would be to calculate, based on 4 cylinders, using half the oil retention of V-8's @ 2 quarts with 2 additional quarts for the remaining mechanicals. A minimum of 4 quarts for the pan (for a high-revving) engine, is where you should start. 4 in the pan, 1 for the filter, total of 5 quarts.
If you look at the pan from the side, you can see it's profiled like a skid plate and IIRC, the pickup, as I recall, is near the center. This means, if you run stock pans, you also need to check the location of the pickup to ensure the pickup is located toward the rear of the sump as possible - not in the middle or forward of the sump.
If I was contemplating your high speed trials; I'd take an old pan and slice it down the middle (front to rear of car; north/south) where the pickup tube intersects, and do a visual to see where everything 'lives'. Or, if you're anticipating turbo return 'ports' for the pan, simply cut the hole oversize enough to see the pickup/pan relationship. Then I'd take my soon-to-be custom pan, remove (cut) the sump out of it, weld a 2" strip/panel into it, and then cut and re-angle the pickup tube rearward for max immersion under acceleration. Also, cut and extend the pickup tube to locate it 1/2" above the pan floor. If you have the pieces already cut and fit, the same shop that TIG's your bung can weld your pan, pickup tube, and baffling for cheap - IF YOU'VE DONE THE CUTTING AND FITTING BEFOREHAND...
One other thing to consider is decelerating; whether or not you kick the car into neutral (coast then brake) at the end of a run, or use compression braking (leave it in gear) and use the engine/brakes to decelerate and stop the car. For the latter, include a provision for baffling to keep the pickup tube immersed when oil can abruptly move to the front of the pan under hard braking...
While the pumps out; put another 2-3 thousands clearance in the bypass piston's bore (factory clearance it TOO tight causing them to stick) and put a threaded allen screw behind the spring for retention, which would allow you to change springs later and 'tune' oil pressures.
I hope this gives you some ideas, and good luck with those high-speed trials.
Southernman
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There are some really good ideas in your post, Southernman! Thank you very much. I do have a spare "shallow" pan that I am willing to cut apart to get a visual impression of where the pickup is in relation to the bottom of the pan.
What I've done to check clearance so far is use a big ball of Silly Putty, stuck to the bottom of the pickup, then push the pan into place, checking the distance from the pickup to the bottom of the pan. I have also used a straightedge spanning the bottom rails of the block, and measured to the pickup, then used the reverse technique to check the depth of the pan.
I have a couple of weld-in -10 A/N bung fittings. I will weld one to the new pan, after checking clearance between the weld bung location and the windage tray, just having a look to make sure the oil looks like it's returning to a good place. I'll also do the modifications to the pickup tube myself.
At Bonneville, there is plenty of room to coast after the 3 mile mark. The conventional wisdom is that the vehicle's brakes are only for loading and unloading the trailer at Bonneville. If you are going so fast that you need to slow down - use a parachute. Otherwise, just coast down and turn gradually towards the return road.
The information about modifying the oil pump for adjustable pressure, and opening the bypass piston bore is valuable. I haven't had one of the oil pumps apart yet, but I do have several of them. What would you use to open the bore? A reamer? Very small hone? I'll have to get one taken apart for an internal inspection.
Steve.
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Steve, I'd ream the bypass piston bore and polish the piston before putting it back together. Purchase a shallow, threaded, allen screw (oversize set screw), drill an tap the hole for the allen screw, replace the spring and piston, and you've got a fully 'tunable' oil pump. Changing the springs wire diameter in either direction will help you optimize pressures for the intended use.
You'll find a driven plug behind the bypass spring, and it takes a little effort, but will pry out of the hole. Every one I've pulled apart, I had to force the piston out of it, due to debris getting between the piston and bore. You'll see scoring and scratches on both once they're apart.
Remember, oil being bypassed is non-filtered oil (actually, oil passing through the pump gears is unfiltered as well, but the pumps are not deep rotor pumps, so it's not a problem for them), but 2-3 thousands of debris between that bypass piston and bore could drive low, or high, oil pressures depending on when the debris gets trapped and seizes the piston...
One other thing regarding your pickup: if you do increase pan depth and pickup to match, be sure to weld some "extensions" from the pickup mouth, that extend down and nearly touching the bottom of the pan (or you can bend short 90's where they do contact the bottom of the pan and have them touching). Logic ? Should you accidentally smack the bottom of the pan, the force will move BOTH the pan and pickup - but not close up the suction window(s) on your pickup. I hope that make sense. If not ping me back and I can send a pick or sketch.
Southernman
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Excellent information. I have a couple of spare oil pumps I can pull apart before attempting to ream the bore of the "real" pump.
I get what you are saying about putting some legs, or "feet" at the end of the pickup tube to keep it from getting smashed against the inside of the pan. Any ideas about how far from the bottom of the pan the pickup tube should be located? (I'm thinking about 1/8" or so).
I'll also take one of the pumps apart with an eye towards drilling and tapping for an allen-head set screw (we have plenty of them at work) to allow pressure adjustments to be made. If the bypass piston bore is close to a standard size, there's a pretty good chance that we will have an appropriate reamer. (I manage a small manufacturing company with an in-house machine shop).
I'll be busy tonight, but should have some time to work on the pickup tube and oil pump on Wednesday evening.
Steve.
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I would keep it up 3/8" to 1/2" or about as big as the hole is in the pickup.
If you take the "freeze plug" out, please drill it for a small cotter pin to go into BEFORE you take it out. That way you know where to put it back to and have some insurance it stays in. It is only held in by the pinched part of the pump and once you take it out it deforms that. Also, if you deform the plug you can open it back up with a press and a socket.
I really think, as I asked before about your oil pan, you were running out of oil to pump. It is always good to over build, but I bet the extra quart of oil will work.
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Looking at that little "freeze plug", stamped cup, it is peened in place. The only way I can see to remove it would be to carefully grind the peened portion of the housing away, which would allow the stamped cup to be removed.
I would love to see a cut-away view of this area, to see if there is a handy place to tap threads for an allen head set screw type arrangement.
To my eye, it doesn't look like there's anything there to D&T a hole into in order to fit a screw.
Southernman - if you could provide a sketch, that would be fantastic. I just don't have a clear vision of what's behind that plug, other than a spring and a piston.
Steve.
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Ok - after taking another look at Southernman's description, I think he is proposing removing the freeze plug, then tapping threads into the large diameter of the housing, which measures 0.738"-0.745" (using a cheap pair of calipers). That's a little bit too big for a 1/2 NPT pipe plug.
It's more in the size range of an M20 fastener, which seems mighty large for a short set screw.
Steve.
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I thought he was talking bout the other end. If I can find my pics I will send you them. I have taken many of these apart and got them working again no issues.
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Got them. This is how I do it.
(http://i1290.photobucket.com/albums/b531/the_man_53/mk2%20engine%202/IMG_20140503_162011_2961_zps1a182107.jpg) (http://s1290.photobucket.com/user/the_man_53/media/mk2%20engine%202/IMG_20140503_162011_2961_zps1a182107.jpg.html)
(http://i1290.photobucket.com/albums/b531/the_man_53/mk2%20engine%202/IMG_20140503_162121_5481_zps208586b0.jpg) (http://s1290.photobucket.com/user/the_man_53/media/mk2%20engine%202/IMG_20140503_162121_5481_zps208586b0.jpg.html)
(http://i1290.photobucket.com/albums/b531/the_man_53/mk2%20engine%202/IMG_20140503_162047_7171_zpsb8656aad.jpg) (http://s1290.photobucket.com/user/the_man_53/media/mk2%20engine%202/IMG_20140503_162047_7171_zpsb8656aad.jpg.html)
(http://i1290.photobucket.com/albums/b531/the_man_53/mk2%20engine%202/IMG_20140503_162800_3521_zps28710b0f.jpg) (http://s1290.photobucket.com/user/the_man_53/media/mk2%20engine%202/IMG_20140503_162800_3521_zps28710b0f.jpg.html)
The cotter pin goes in the hole, any questions
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It looks like I'm using the same pump (Schadek)?
(http://i468.photobucket.com/albums/rr44/Jetmugg/Oilpumpbottom_zps9204ec45.jpg)
Thanks for the pics, Lucas. I assume you run the drywall screw into the hole in the end of the plug, then pull it out with the vise grips, correct? Cross drilling for the cotter pin is a good idea - thanks for sharing.
At that point, what do you do to the OD of the piston and/or the bore of the lower pump housing? I'll have to check and see if we have a hone small enough to get into that bore, but I doubt it. I can polish the OD of the piston to let it slide a little more smoothly if that's an issue.
As to what Southernman was talking about, I don't see a handy way to add a setscrew type of adjustment, apart from making a solid plug for the cap end, then drilling and tapping it. I don't really think I need to go to that extent with the current setup.
Steve.
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Yeah if you don't drill before you pull the plug you don't have a shot at getting it back to where it was. I personally don't cut down the surface of the pump or piston intentionally. I just clean it out and smooth out any burrs. Then I put it back together. If anything I would try to cut the od of the piston out by the "freeze plug" and leave the initial od alone. All of these I have torn down just have a little build up of metal and after that metal eats the pump housing a bit and you clean it out I haven't had an issue. Make sure to take shop air and make the piston function. Try to make it stick, rotate it, and keep doing it. Once you have a feel for it you will see if and where it was getting hung up and make adjustments accordingly.
That pump pictured is the one I run in the mk2 jetta I have. It runs maybe a tick over 50lbs when hot and redline, 15lbs at hot idle. Redline being 6,000rpm and figuring 10 psi for every 1,000 rpm is about right. I have always ran the windage tray and haven't had any issues...but I run better oil, lol :D
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by the way good luck at Bonneville, hope you get hi-rpm oil pressure by then,,
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Hey guys, sorry for the delayed response.
I like how theman approached this tweak, and it certainly would be a more conventional approach. Also, the oil pressure numbers appear to be right on the mark.
I'm kind of fortunate that I have access to a full array of machining equipment (Mills, lathes, CNC equipment, etc), so the threaded plug arrangement would be my approach (match the D&T to the hole, then use a lathe to trim and recess the threaded plug to match spring OD), since the cotter pin can 'work' in the hole over time, and you'll end up with a small 'controlled' bleed somewhere down the road. Not a big deal.
The other reason I'd ream the bore is, as theman suggested, rotating the piston around to 'find' high spots means there's been some distortion within the hsg itself. You can keep rotating and sanding until you achieve smooth operation, but setting the pump up on the mill and reaming a couple thousands will accomplish the same thing - but guarantee straightness of the hsg bore.
Either are good solutions, but the reason I prefer the plug is to permit 'tuning' of the spring itself, without working the pin holes each time you change the spring out. Themans solution would work fine on my street driven vehicles providing the pin holes don't wallow and/or pin break (I'd have to rely on his experience with longevity of such mods), and the other is suggested for high rpm/race consideration (i.e. if you wanted to try near 0w/10, 0w oils or similar synthetics, to pull a few more horses out of it, you could use the bypass springs diameter, length, and rates to dial it in).
Good discussion guys and thanks for all the great ideas.
Southernman
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The cotter pin is really just insurance when I do it. The pump bore is pinched at the "freeze plug" end and holds it well all by itself. The cotter pin is just there in case while pulling it out and pressing it back in the bore or plug gets distorted. This is the same oil pump out of my last 1.6 build that had 40,000 miles on it and this build has about 7,000 on it. I had some issues by accidentally smashing a wire in the vac pump and it didn't sit right. Long story short I had to pull this pump and clean it again. The cotter pin is fine. If done the way mine is done I would see no issue to run it for a million miles. Especially considering how the stock setup is just held in by the pinched end of the housing.
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I've been hectic-busy for a little while, but got the engine put back together over the weekend. I polished the oil bypass piston using metallurgical polishing equipment, and polished the bore of the bypass section as well as I could without specialized equipment. The piston moved very smoothly at that point, and I verified movement with an air compressor and rubber nozzle.
I used Theman's cotter pin technique to set the position of the plug, and allow re-installation in the same position relative to the pump body.
The home-spun baffled pan, extended pickup tube, and angled turbo return fitting, and windage tray were all installed using brand new socket-head, integrated washer bolts from McMaster.
I added 4-1/2 quarts of Mobil 1 15-50, and a fresh Bosch 3421 filter before firing it up. I let it idle and warm up a while before giving her some rpm's.
I held the rpms between 5500 and 6000 for what seemed like an eternity, with a few short trips on the high side of 6000. The oil pressure held steady as a rock at about 65 psi, and never bobbled a bit.
Thanks for all the suggestions. I feel pretty good about the engine right now, and the real test will be in less than a month.
Steve.
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I could be wrong but I don't think that is the correct filter. I think that is the gasser filter, which I have heard has 1/2 the burst rating of the diesel filter and some other stuff I cannot remember, all of which I cannot confirm, but hopefully someone will know and have proof. I use 068115561E it is a mann filter for the ahu and is supposed to have higher burst rating and bypass pressure than even the regular diesel filter. Also, I have always needed 5 quarts for an oil change with the 4 quart pan. The bosch number I got when searching was 72199WS or 72150 for the diesel filters
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As a side note, in the gasser world bosch oil filters are known to cause the oil light to go on. I personally had this happen. They are in the same quality department as FRAM filters nowadays.
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Hmmm - very good information. I've been using that filter part# since I fired this engine up for the first time. Between break in, inspection, and having the pan off, I think I've used 3 of them. It's my fault for not double checking, just relying on the # that the parts counter guy quoted.
One nice feature about that filter is that it's a slightly smaller outside diameter, which helps it clear the center front motor mount. That's probably not an issue for OEM Volkswagen applications, but I am using a Dodge Omni style front mount. At one point, I bought what I thought was the correct filter for the application (non-Bosch), but the outside diameter was too large to clear the mount. The filter would not thread onto the oil cooler adapter due to that interference.
Sounds like I need to do some more research to find a "diesel" oil filter that will work.
This place is a wealth of knowledge!
Steve.
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As a side note, in the gasser world bosch oil filters are known to cause the oil light to go on. I personally had this happen. They are in the same quality department as FRAM filters nowadays.
Things that make you go....hmmmmmmm. I wonder if I was suffering from just such a condition.
Steve.
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It sounds like maybe your revved it out of gear. If that's the case, you should test it driving under load with the two significant differences being where the oil sloshes in the pan and the turbo spinning a lot faster.
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068115561E is what I use, also some numbers to check would be 068115561BML or 068115561B
I get them from autohaus https://www.autohausaz.com/index.html
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Here is a bit more reading about the oil filters recommended for gas vw's in case you are wondering :)
http://www.cabby-info.com/engine.htm#Filters
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It sounds like maybe your revved it out of gear. If that's the case, you should test it driving under load with the two significant differences being where the oil sloshes in the pan and the turbo spinning a lot faster.
Unfortunately, I don't have any handy locations to run 125 mph for a distance. I think the at-speed testing is going to have to wait for Bonneville.
Steve.
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I'm not talking about going 125. You can see in your video @ 0:59 that it starts to do it in second gear. Can you legally drive it and wind out second? That would tell you a lot more than revving it in neutral with the car standing still.
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It's "plausible" to run out 2nd gear on public roads, but I'd also have to file it under "likely to result in a conversation with John Law".
I'll have to work up some courage for that one.
Steve.
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It's "plausible" to run out 2nd gear on public roads, but I'd also have to file it under "likely to result in a conversation with John Law".
I'll have to work up some courage for that one.
Steve.
If you are otherwise legal remember they work for you, not the other way around. Just keep it in posted speed you will be fine.
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The truck is technically legal, (valid plates and insurance), although it has absolutely no lights, and the windows don't roll down, which make even basic hand signals impossible.
Steve.