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Engine Specific Info and Questions => IDI Engine => Topic started by: camboscams on August 25, 2011, 03:05:56 pm
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So here's the deal, I've already smoked one VNT15 in less then 200 miles. I rebuilt it myself with a Gpop shop rebuild kit. with that turbo after 75 miles or so it started smoking badly and soon it finally started to rub the housings after 150 miles. so i purchased a new center section from Gpop and got it installed last night. I did all the things Jim told me to do, like checking my oil supply and return. I blew into my oil return and could hear a little bit of a gurgle but that was with the car on jack stands on the front too so on level ground i would think that the return would be above the oil level. I've got a -10an bung welded as high as i can on the oil pan close enough i could weld the top of it from the outside, just like every other TD conversion out there. Now the oil supply i removed the vacuum pump and primed the engine (an 11mm 6pt socket works well to do this) until i had oil coming out of the supply line and it was as good a flow as i could produce by hand. I then did this again once the line was connected to the installed turbo. And i let it idle for at least 5 minutes upon first start up SO (pardon my rant) i drove the car last night for a short test drive and it didn't seem to smoke when i got home (So far so good) but it was night so im not 100%. Then for today's ass kicking, i was removing my intake tube for some minor alterations and noticed quite a bit of oil in the tube, like more then normal turbocharged engine amount. The outlet of the turbo seemed pretty dry so i thought maybe it was some residual oil left int the tube, so whatever, i cranked it up just for kicks to see if there was any down in the compressor housing and started to raise the rpm and it started blowing a good amount of black engine oil out :(
Does anyone have some input? I'm waiting on a grommet for my pcv grommet for my g60 valve cover to drive it again but that should be tomorrow. I'm at a loss and i'm really leery of destroying this turbo so please understand my reluctance. And again sorry for my rant if you've made it this far...
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Since you don't have a grommet, what are you doing with the hole in the valve cover mean whilst?
Did you try disconnecting the oil return line and seeing how much oil is leaving the turbo?
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Since you don't have a grommet, what are you doing with the hole in the valve cover mean whilst?
Did you try disconnecting the oil return line and seeing how much oil is leaving the turbo?
For now the hole is loosely filled with the oil separator which then goes to the pre turbo intake tube. So i would think that i would have even less crank pressure then normal. so i would think that would help rule the high crank pressure blowing the oil past the seals problem.
And i have not removed the return and watched how much oil runs out. What would that help me tell? Too much oil flow?
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It would let you know how much oil is being supplied to the turbo.
I'm not sure how much is supposed to flow at idle.
It would let you know if you need to install a restrictor in the oil supply line,
It would let you know how much block pressure is trying to escape through the turbo.
I think the block pressure can be higher than cranckcase pressure inside the head. Do you have a block vent (other than at the valve cover)?
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Okay i'll try that today. And as far as a block vent i have none. The vacuum pump is still has its factory outlet going into the block. Would that add much pressure to the crankcase?
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my 1.5TD used to blow oil out of every orifice and seal.. and being that 1.5D's have no dip stick tube (dipstick seals directly to the block with a felt o-ring) at all, you know where most of the mess was on that engine..
anyways, that engine never blew oil thru the turbo oil seals, and it had a crank case vent, and a valve cover vent (both had catch cans, and were basically road draft tubes.. even with all the vents, that engine still had LOADS of blow by when it boosted up.. at idle, take the cap off and there was basically nothing.. the cap would dance around on the valve cover a bit, but nothing horrible. on boost, it would blow a solid stream of oil out the valve cover (if you forgot to put the oil cap back on)
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Did the new centre section include the shaft/compressor/turbine? If not I would be looking at an out of balance issue.
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New everything, for the center section.
Yea i'm wondering if i should vent the crankcase, from where the vac pump goes into the block, to the intake tube. I got my linkage done and it runs nice!! i didn't even break 1000 degrees once going over 15psi. so we'll see. im going to take my intake tube off and instect for large amounts of oil. there was zero smoke so i'm thinking there wont be any oil.
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So i removed my oil return and watched the mount of oil leaving the turbo and it seamed like a good amount but it was coming out of a -10an return line and it wasn't anywhere close to filling it. It has coming out about as fast as you could pour cold 15-40 through it. My only other concern is that the oil return below the level of oil. But doesn't everyone's?? Its 5/8 return line does that compensate for the fact that its below the oil level?
On another note that thing spools fast!!! All i have is a linkage from the injection pump to the vnt arm. its a 1:1 ratio for now and i don't have an actuator to limit the boost yet so i can't even lay into it much or its over 15psi like instantly! I'll try to post some pictures maybe start a thread for the whole conversion soon
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So i removed my oil return and watched the mount of oil leaving the turbo and it seamed like a good amount but it was coming out of a -10an return line and it wasn't anywhere close to filling it. It has coming out about as fast as you could pour cold 15-40 through it. My only other concern is that the oil return below the level of oil. But doesn't everyone's?? Its 5/8 return line does that compensate for the fact that its below the oil level?
On another note that thing spools fast!!! All i have is a linkage from the injection pump to the vnt arm. its a 1:1 ratio for now and i don't have an actuator to limit the boost yet so i can't even lay into it much or its over 15psi like instantly! I'll try to post some pictures maybe start a thread for the whole conversion soon
as long as you keep it under 25 psi, you should be fine.. the turbo should only make 20-25 psi maxed out with the vanes open. but if you shut the vanes, it could make enough boost to blow the head off..
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Well first off i can't run more then 15psi due to my setup, and when i have my vanes in the least boost position i can only make 6 psi at the governor with full pedal.
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Well first off i can't run more then 15psi due to my setup, and when i have my vanes in the least boost position i can only make 6 psi at the governor with full pedal.
why can you not run over 15 psi??
i ran way over 15 psi to a bone stock 1.5 TD..
and if you can only make 6 psi full pedal with the turbo open, then you have no fuel to spool it..
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I can only run 15psi because i'm running a 1.6 rotating assembly in a 1.5 block and head, so the added volume coupled with the smaller combustion chamber pushes my compression ratio upwards of 25.5:1. And i've had to put several headgaskets on this engine and i'm tired of it. So until i can get another block together i'm going to take it easy on the boost.
And for the fuel since there is no global measurement of how much fuel i'm putting out, all i can say is its a giles super pump, and with the old turbo i could hit 1400 degrees and more in no time and all the while rolling coal. So since i have no comparison to how much fuel your running you must have way more then me.
But anyways, why am i getting the amount of oil in my intake that i'm getting? I just don't get it
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Forgive me as I have not read the entire thread but are you rerouting your CCV back into the turbo inlet? If so, do ya think thats the oil thats in your intake?
If you are rerouting your CCV back into the intake, why?
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You have me second guessing myself now, i've only been doing it cause that's how it was done when it was N/A. I've considered doing like a road draft setup, but i guess i could just put on of those small filters on it and let it vent to the atmosphere. That would eliminate the issue of too much crank pressure.
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You don't have to route it to the road to get rid of the CC vapors, if you have the room in your engine bay, add a catch tank and then reroute the vapors back to the turbo inlet. Also if you do add a catch can, depending on where you mount it and if you want the excess oil to drain back to the block or just empty it every so often.
I on the other hand, vent it out to the ground but later plan to do a catch can with no return.
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You don't have to route it to the road to get rid of the CC vapors, if you have the room in your engine bay, add a catch tank and then reroute the vapors back to the turbo inlet. Also if you do add a catch can, depending on where you mount it and if you want the excess oil to drain back to the block or just empty it every so often.
I on the other hand, vent it out to the ground but later plan to do a catch can with no return.
x2 on the road draft setup, thats how im running mine. i would not just put a filter on it and vent it to the atmosphere.. you want it to go towards the ground, or towards the sky.. diesel blow-by is stinky stuff..
and your intake will always have oil in it.. the seals in a turbo are not exact enough to keep every single spec of oil within the center section of the turbo.. i have a road draft tube on my car, and a turbo, but i still get oil in my intake.
i really dont understand why everyone is soo worried by a little oil in the intake?!
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I don't get 15 with the vanes open either,.. but got 35psi with the vanes closed if I wasn't paying attention.
I still don't have a good idea of how much oil drained from the turbo over a certain length of time.
The vacuum pump will actually pressureise the block if there is a vacuum leak.
You also didn't give much info about how much gasses were coming from the port on the oil pan when you removed the turbo drain.
The inside of the turbo will be at the same pressure as the block.
Even though ROR had huge block pressure and claims no extra oil coming from the turbo,
he's not concerned about oil from the turbo.
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weird.. am i the only one who gets 15 psi with my vanes open?
i know they are WIDE OPEN.. i took the turbo apart to open them since they are stuck.
yes, if the vanes are closed, you DO get 35 psi in a hurry..
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I don't get 15 with the vanes open either,.. but got 35psi with the vanes closed if I wasn't paying attention.
I still don't have a good idea of how much oil drained from the turbo over a certain length of time.
The vacuum pump will actually pressureise the block if there is a vacuum leak.
You also didn't give much info about how much gasses were coming from the port on the oil pan when you removed the turbo drain.
The inside of the turbo will be at the same pressure as the block.
Even though ROR had huge block pressure and claims no extra oil coming from the turbo,
he's not concerned about oil from the turbo.
Well as to the gases coming out from the pan end of the oil drain i have no idea. as the oil return is below the level of oil and it was plugged. It may have been due to the incline and the fact that it was jacked high enough for me to slide under it. But the line from the block going to the vacuum pump is disconnected so it has every chance to not be under much pressure.
And yes ROR apparently so. You must have an anomaly
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I don't get 15 with the vanes open either,.. but got 35psi with the vanes closed if I wasn't paying attention.
I still don't have a good idea of how much oil drained from the turbo over a certain length of time.
The vacuum pump will actually pressureise the block if there is a vacuum leak.
You also didn't give much info about how much gasses were coming from the port on the oil pan when you removed the turbo drain.
The inside of the turbo will be at the same pressure as the block.
Even though ROR had huge block pressure and claims no extra oil coming from the turbo,
he's not concerned about oil from the turbo.
Well as to the gases coming out from the pan end of the oil drain i have no idea. as the oil return is below the level of oil and it was plugged. It may have been due to the incline and the fact that it was jacked high enough for me to slide under it. But the line from the block going to the vacuum pump is disconnected so it has every chance to not be under much pressure.
And yes ROR apparently so. You must have an anomaly
weird.. and i was starting to think that my turbo might be needing a rebuild in the future.. im just gonna leave well enough alone for the time being. it doesnt smoke, and it still boosts hard.
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I read you use a g60 valve cover. Just makin sure your using the plastic cover that MK2's and up came with. If you don't have that with the G60 cover you'll be using a large amount of oil; by my experience anyway.
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Good point, i do have the valve cover baffle that rests on top of the cam retaining cap studs.
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So if for whatever reason i'm blowing oil past my seals will it damage them or damage the bearing assembly in anyway?
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For testing purposes just vent the valve cover to atmosphere. Also make sure the intake is plugged anywhere it could put boost back into the block.
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So if for whatever reason i'm blowing oil past my seals will it damage them or damage the bearing assembly in anyway?
run a vent from the front of the crank case, off that port where the vacuum pump blows back in. vent both of those to a LARGE catch can, or the road. make sure you use atleast 1/2", or 5/8" internal diameter tubing..
thats what i had to do to my 1.5TD.
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my opinion only - take with a grain of salt; but I find (my 1.6 only has about 15000mi on it, since new pistons, proper re-bore,etc) that over 18-20 lbs of boost, crank pressure increases exponentially. I've had my oil dipstick come out once around that pressure and it's a relatively new engine. I went to 1" diameter hose from the valve cover back to the intake and not had the oil level drop at all since changing to a larger hose. Although I don't know if that's helped, but I think going from 1/2" or 5/8" hose to 1" has to allow more venting. I also keep my max boost below 20 psi as well with the VNT.
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your rings definitely are NOT seated perfectly to the bores either.. so thats letting a little extra blow by in the crank case..
yes, i feel that if you stay below 20 psi, its easy to keep the oil in the engine, and keep the blow by levels low enough to manage..