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Engine Specific Info and Questions => IDI Engine => Topic started by: Orb95 on October 28, 2015, 12:00:43 pm
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Anyone know what the stock setting for the fuel screw is on the injection pump? Just finished rebuilding the motor, but it is having a hard time starting and once idling smokes like crazy. I don't know why it's smoking so bad. I had it turned up slightly before i took the motor out. Just want to get back to basics to start troubleshooting the smoking/starting issues.
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There isn't really a "stock" setting. A pump shop would set it by throwing the pump on their calibration machine and adjusting it till the pump was outputting the amount of fuel the spec sheet says it should. Since you can't possibly do anything like that yourself it's more of a "figure out where you have the right mix of performance, smoke and fuel economy for your needs".
Smoking at idle and hard starting implies incorrect timing, not anything to do with the fuel screw. Is the smoke white? Does it burn your eyes? If so you probably need to bump the timing up. Where is it set to now?
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WHAT in the world do you mean by "just rebuilt?"
You mean this engine has just been put together and never ran (as in no break-in).
Or do you mean you have a few hundred intelligent miles on it post break-in?
If it is a brand new engine, you are doing a wonderful job to ENSURE the rings never will seat if you are standing there letting it idle. You just don't DO that.
And, seriously, exactly what do you mean by rebuilt? Some of these guys empty the ash tray and call it a rebuild.
Any engine I rebuild will smoke due to the use of slight amount of lube for the bores and non-seated rings and some assembly lube here and there and all kinds of stuff to burn off in the first 10 or 15 miles.
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Well thank you for the replies. Anyway to answer your questions, it is white thick smoke that burns the crap out of my eyes. I set the IP to 1.00mm as the bentley manual calls for on turbo engines. To answer Dakotakid's questions, yes it is brand new just rebuilt no break in, no miles on the engine yet. As far as what has been done to it, bored and honed for .020 over pistons, new valves, valve seals, valve seats ground and lapped, valve clearance adjusted, gaskets all around, and new injectors. This is one of my first rebuilds and would like any suggestions on how to seat the rings best.
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When you let the new rings slide up and down that new bore, without load, you are essentially polishing the cylinder walls smooth. You are defeating the hone.
After rebuild, it is honestly best to only idle it enough to rule out any immense oil leaks, etc. Once that is quickly determined, drive off with the car or whatever vehicle the new engine is in. If you have the option of having a girlfriend or wife or other friend follow you in their car, that is great. It is a nice safety net.
Simply take that new engine and start getting load on it. Throttle up (like on a scale of 10) (like the pain scale in hospitals) to a 7 or even an 8 and let it pull for a few seconds. Then get off the throttle for a bit....and then right back on the throttle, etc. What you are doing here is getting those rings to expand outward from the pistons and allowing them to mate and stabilize themselves in the bore.
Occasionally, briefly stop the car in a safe place and look under it to check for leaks or whatever. Then, get right back in and drive some more.
Not only do you polish the cylinder walls with prolonged idle, but, the rings can actually "migrate" on those pistons and work to align the gaps....which is exactly what you do NOT want to do.
For me, I work on my engines in a community which is at the geographical base of some pretty rugged old mountains (the Black Hills). There are a lot of steep climbs with "s" curves and then down-hills. I take that new engine up there into those "challenging" roads and run it through it's paces to seat those rings.
Goetze rings are so cool, because you can literally feel that engine get stronger within like 10 miles (rings seating) out. I don't have anyone to follow me and there is always a little risk on my end that I may be walking or hitching a lift home if all does not go well. However....it always has because I pay attention to small details in the rebuild.
Don't forget to monitor your temperature and everything else on that initial voyage. It is a truly exciting time!
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While taking too long to seat the rings and ending up with glazed cylinders is certainly a real possibility, so is overheating the rings and causing them to lose their temper and never seal. When the cross-hatching is fresh, placing too much load on the engine for too long can do exactly that. Short bursts of power with time off the pedal is necessary. The short burst presses the ring against the cylinder, the time off the pedal lets the ring cool down. This process should also be done after you have driven gently until the engine has come up to normal operating temperature.
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White, acrid smoke is usually unburnt diesel. Did the injectors come from a reputable source? Did you use new heat shields? Maybe due a compression check to make sure something did it get screwed up on reassembly.
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I found that the IP timing was retarded because iI forgot to preload the dial indicator, so i corrected that, but it is still smoking terribly. Yes, Rallydiesel, I did do a compression test before taking it for it's first test drive, all the cylinders seemed too low, and were as follows when I tested the motor cold:
Cylinder #1 350psi
Cylinder #2 365psi
Cylinder #3 340psi
Cylinder #4 360psi
I did use new heat shields every time I have re-torqued the injectors and have them installed the right way. The injectors are Bosch OEM remanufactured I had my local parts store order in for me.
I took the car out for a test drive today and put about ten miles on it, doing what was suggested, bursts of power, but it is still smoking like crazy. It starts better now that all the air is out of the system, but seems to shutter and bog down as I let off the accelerator and push the clutch in to change gears. It has stalled when doing this, but i assume its a simple idle adjustment.
Is this normal to have this low of compression on new rings? Does this also take more than 10 miles to burn off any assembly lube or oil in from assembling the engine?
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Did you measure piston protrusion with the new pistons? Just wondering if the head gasket is the right thickness.
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I did not, I used the gasket that came in the rebuild kit with the oversized pistons from parts place inc. The previous owner did some work to this motor because it has a 12mm Topline mechanical head on a stock VW block, engine code CY . It seems to be an aftermarket head put on at some point, not sure why. I will have to check the old gasket for the notches
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It is normal for there to be low compression before the rings seat especially when the engine is first running. It is also normal for there to be lots of smoke on a first start and lots of smoke if the air is not purged or there is air continuing to get in the fuel. Did you adjust the valves? If not, then that can lower the compression further.
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Topline heads are good items. I have yet to hear anyone complain about them.
It is getting hard to find a good VW head anymore. It is probably a rather fresh head.
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yes, libbydiesel, new valves, valve seats were ground, lapped, and adjusted. Just saw that the old head gasket was a 2 notch.... if the motor really needs a 2 notch but I installed the 3 notch that came in the kit would this be the cause of all my problems? Would the motor even run if I installed too thick of a gasket? I guess I won't know unless I pull the head off again....... >:(
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It will run ok with a gasket that is too thick but it will add to your low compression. Regardless, I think your results are probably normal for an engine that has not had the rings seated. I'd move on with seating the rings and circle back to compression if necessary. Is there air entering the pump on the supply side?
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Not sure if air is entering the system..... previous owner has rubber lines on everything instead of the clear tubing. Does anyone know where I can get the clear tubing to run to the IP inlet, and between injectors?
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I will continue with the break in, does anyone have a clue how long this could take? It's pretty embarrassing driving down the road and killing every insect in the Tri state area
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Is there air entering the pump on the supply side?
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I don't know if there is air getting in the system because all of my lines are rubber from the previous owner. The rpms are surging up and down at idle right now, so that could definitely be air in the system.
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It is normal for there to be low compression before the rings seat especially when the engine is first running.
and lower if motor is cold too
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I don't know if there is air getting in the system because all of my lines are rubber from the previous owner. The rpms are surging up and down at idle right now, so that could definitely be air in the system.
Then step one is to replace the supply and return lines with clear.
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the rubber lines po put on is a sign you need to check for leaks, you can, until you get clear line, get new rubber line and clamps and run, i ran from return too. the inlet needs a reducer to size, or adapter. inlet is like 1/4" and fuel line is 3/8", normally.
after 10-20 miles engine will start breaking in, full break in (after full rebuild) can take 5000miles, with oil changes. rings will seat in 500-1000miles. you should get less oil smoke in a few miles. and have little after 200 or so miles.
your stalling and rough running sure sounds like air in fuel system. pump main seal is usual culprit. since you had timing bolt on pump open, it had a copper washer right? if it was already in there it may need extra tightening, check stuff like shutoff solenoid that its not sucking air in, fuel leaks on pressure side, which should be obvious.
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Did you adjust the valves?
mech head or hydro? you need shims to adj valves, and tool
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This might not be the most popular suggestion, but at this point, I would try changing the pump timing while the engine is running. I used to have a 1.6td that ran much better at a signicantly more advanced setting than normal. I would loosen the timing bolts and leave one just tight enough to move the pump by hand, then start the car and try slowly tilting the pump towards the engine. If the engine starts to run smoother and the smoke clears then you found the problem. If it starts to get louder and more metallic sounding then stop and go back to the stock setting.
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Well, if you are going to encourage him to time it like this, you have the responsibility to inform him how to take the stress off his fuel lines after rolling the pump around like a chimp with a coconut!
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Ha!
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if motor is running and/or injection lines are tight, pump will turn very little until lines bind. loosen and retighten all 8 line nuts. both sides of each line need to be loosened before retightening, so i loosen all 8--,,
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It is a mechanical head, the machine shop set the valves as to my bentley specs. What i have recently noticed, the previous owner bolted the fuel filter to the rain tray above the turbo, and is on a 45 degree angle. I try to crack open that bleeder on top of the filter flange while the engine is running and no fuel comes out, the motor only dies. With the way the filter is positioned I think there is a pocket of air at the top of the filter, is there an easy way to get this out? Maybe trying to put it back to it's stock position would be best.
If the hardened lines are cracked loose while the motor is running to time the pump by hand, won't it leak and run like crap?
On another note anyone have any tips for getting glow plugs to seal? There are bubbles leaking from around the threads, took them out, cleaned the threads good, threaded them back in, but still they leak.
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You loosen the lines to relieve stress after adjusting the timing and bolting the pump back up. It's a critical step, I personally had a line break after not doing that.
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IF there is air entering the pump then it messes up the timing. Trying to time by ear before making sure there is not air infiltration is counter-productive. Do not be distracted by hillbilly pump timing at this point in time. You run the serious risk of running the engine at low load long enough that the rings will never seat.
Step One: get clear lines on the supply and return.
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Well stupid me discovered the cam timing was a tooth or two off somehow. I thought it was all adjusted and correct, something clearly was not.
NOW that the cam is adjusted CORRECTLY the motor is running better! ;D I have higher compression numbers, in the low 400's. And is producing black smoke on acceleration, not that disgusting white raw diesel. I have the clear tubing on order, should be in soon, then I can determine if I am getting air in the system. I'll update tomorrow when I take it for the first ride after adjusting the cam.
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Awesome!
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How do you get the cam off 'by a tooth or two'? Setting the cam timing is *THE MOST CRITICAL* procedure to perform on these engines. If you follow the correct timing belt procedure it is impossible to have the cam timing off at all. The correct procedure even includes rotating by hand back to TDC for #1 and re-checking the cam timing so even if it was off at first there is no chance of even cranking over the engine with the cam timing off. Off by two teeth will typically mean the pistons were hitting the valves. Often after getting tapped by the pistons, the head of the valve will fall off a few thousand miles later. If you can't/don't follow the correct procedures then you don't have the capacity to maintain one of these engines and your vw diesel car ownership experience will be fraught with disappointment and frustration. My best and kindest recommendation is to either step your game up a couple notches, pay someone else to work on it, or sell it off.
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I couldn't tell you how the timing was off. I followed Vince Waldon's and the Bentley Manual's procedure. Rotated the motor by hand two rotations and everything lined back up perfectly. Not to mention it all turned nicely, no binding. Unless the belt jumped time, or the cam gear slipped on the tapered shaft. I will admit this is my first VW diesel full rebuild, but not my first rodeo. I certainly will have to "step up my game" Because clearly it is not "good enough." These forums are here for people to troubleshoot problems and discuss their vehicles. Not for cocky people to insult those in need of help.... Hey i don't know, maybe I'm wrong.
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I did not insult you or at least didn't intend to. If you want to take it that way, it's up to you. My post was offered as an attempt to assist and was the best advice I could provide given the circumstances. It was an objective assessment without any malicious intent whatsoever, in fact the intent was the opposite. When you see someone poking a sleeping tiger, the best advice you can give is to run and it won't help anyone to word the advice gently. If you don't care to read my posts, you are welcome to add me to your 'ignore list'. If you need the step-by-step on how to edit your ignore list, let me know and I'll happily oblige. Good luck with your project.
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........It's pretty embarrassing driving down the road and killing every insect in the Tri state area
I'm in Queens where you at? I have a diesel pulse adapter/ timing light and can check the timing for you.