Guest das280zx Posted June 17, 2004 Share Posted June 17, 2004 Well I have had my turbo engine in my zx for about a year and a half. Since the swap, it has always smoked profusely on start up. Everybody says it must be my valve guides, or seals, but I don't really know. I had a local shop re-build the head before I put the engine together and it was my understanding that they replaced the seals and such. I think it is getting around the turbo, but don't know how to test for this. Well there is alot of oil pooled up in the turbo when you take the j-pipe off. Maybe a couple of cc's. Oil also pools up at the base of the compressor inlet. You would think this would be from the turbo, but could it also be from the valve-cover vent? I wouldn't think this much oil could be sucked throught there. The turbo seems very tight and I took it apart about a year ago and replaced all the seals and stuff, but it still does the same thing. The smoking is really only bad on startup, and after it has been off for a while. Recently I had oil gauge problems, so I hooked up a mechanical gauge to the motor, and it was pumping somewhere north of 60 psi at idle and well over 90 at anything much higher than that (this is with the engine cold btw). So maybe I have too much oil pressure and it is blowing by the turbo. I thought about putting some sort of pressure regulator on the turbo oil line, but this kind of scares me. Anybody got any ideas. Sorry for the long-winded post, but this problem really bothers me. Quote Link to comment Share on other sites More sharing options...
wheelman Posted June 17, 2004 Share Posted June 17, 2004 That oil pressure seems a bit high, what is it once the engine warms up? Wheelman Quote Link to comment Share on other sites More sharing options...
Tim240z Posted June 17, 2004 Share Posted June 17, 2004 Try a lighter grade of oil..... Quote Link to comment Share on other sites More sharing options...
Guest das280zx Posted June 17, 2004 Share Posted June 17, 2004 no, the engine wasn't warmed up, I was just testing to see if my gauge was really broke (it was). I use 10w30 mobil 1, but I have used 5w30, it all seems to smoke the same. Once the engine is hot and warmed up, it will not blow smoke, unless you idle for a long while and then revi it up, then it blows smoke. If it has been sitting, it will blow a large cloud of smoke on start up, and then will blow smoke if you rev it up for a while, and then nothing. So I think it is just blowing the oil out of the turbo, and when it gets most of the pooled oil out, it doesn't smoke as much, or not at all. Will leaky valve seals have the same symptoms? Quote Link to comment Share on other sites More sharing options...
240hoke Posted June 17, 2004 Share Posted June 17, 2004 my car blows smoke after letting it idle for a while and then reving it up. I just figured it was worn rings or bad gap. Lemme know if you figure it out. Ive tryed regular oil and synthetics from 10w-30 to 15w-50 and havnt really noticed much of a difference. Im runnig mobile1 10w-30 right now. -Austin Quote Link to comment Share on other sites More sharing options...
Afshin Posted June 17, 2004 Share Posted June 17, 2004 Burning oil at start up and after idling for a few minutes is classic fo faulty valve seals/stems. For turbo's, more often, it smokes more under load and boost, not at start up and idle. Oil pressure is less at idle, so if it's smoking after idling (and warm engine) for a while and not with high RPMs I would figure that it's less likely to be from high oil pressure. Have you had the chance to check compression in all cylinders? Quote Link to comment Share on other sites More sharing options...
Guest das280zx Posted June 18, 2004 Share Posted June 18, 2004 Burning oil at start up and after idling for a few minutes is classic fo faulty valve seals/stems. For turbo's' date=' more often, it smokes more under load and boost, not at start up and idle. Oil pressure is less at idle, so if it's smoking after idling (and warm engine) for a while and not with high RPMs I would figure that it's less likely to be from high oil pressure. Have you had the chance to check compression in all cylinders?[/quote'] Yeah, I checked the compression when I first got the engine going. It was about 135-140 psi accross the board, which I guess is pretty standard for the turbo engine. The engine only had 100,000 miles on it. Quote Link to comment Share on other sites More sharing options...
fl327 Posted June 18, 2004 Share Posted June 18, 2004 sounds like its your turbo because theres a good amount of oil in the j pipe. Quote Link to comment Share on other sites More sharing options...
Afshin Posted June 18, 2004 Share Posted June 18, 2004 Oil in the J pipe can be from either the turbo or high backpressure as caused by a faulty PCV valve or clogged line, so check those. While it could always be the turbo, as I said earlier, it is usually does not smoke with start up and if your turbo bearing was leaking oil from a year ago, I would expect it to have failed by now. (I have seen some oil in the J pipes in cars with working turbo's and without smoking or any noticeable problems) Why don't you try cleaning the J pipe, check to see if any oil is present in the manifold right after the throttle plate. Put it back together start her up and see if she smokes at start up. At that point there is no oil build up in the manifold to cause smoking. If it still smokes, likely the valve seals and then check and see if oil is accumulating in the J pipe. If not smoking and/or oil acumulates quickly in the J pipe, it may be the turbo. Don't forget the test your PCV hose/valve. No harm in rechecking the compression as well, a lot can happen in a year. I assume the spark plugs look well ? Quote Link to comment Share on other sites More sharing options...
Guest das280zx Posted June 19, 2004 Share Posted June 19, 2004 Afshin, That is a good idea. I think I will clean out the pools of oil and then try and start the car. Maybe first I will check the pcv valve though. thanks for the good ideal all. Dave Quote Link to comment Share on other sites More sharing options...
Guest BigE Posted June 19, 2004 Share Posted June 19, 2004 Check your oil level and oil line. If the turbo does not have a clear drain into the pan, it can force oil back up the line and past the seals. The oil line should gravity drain via a direct path to the oil pan. The level of oil in the pan should not cover the turbo oil drain outlet. Quote Link to comment Share on other sites More sharing options...
Guest bastaad525 Posted June 22, 2004 Share Posted June 22, 2004 ugh... can anyone say just how high over the "H" mark on the dipstick the oil would need to be to cover that turbo drain? I'm not having any smoke or anything, but I did overfill my oil a few weeks ago and havent had a chance to drain it... it's about 1/3 of an inch above the H... Quote Link to comment Share on other sites More sharing options...
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