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Engine Specific Info and Questions => IDI Engine => Topic started by: DJPyro on April 07, 2011, 08:36:29 pm
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The subject pretty much sums it up.
I've got about 2500Km on a new set of rings, done in-frame, cylinders were deglazed and given a good crosshatch. Car seems to be generating a lot of crank case pressure, but not a lot of smoke out the oil cap, just air.
Also, it runs fine when it's cold but once it warms up the revs tend to hang a bit on shifts, and it smokes more under accel off idle. I'm hoping it's just valve guides/seals since I plan on refreshing the head in the next few months, but having just recently lost my job, I can't really afford another rebuild right now.
Any thoughts?
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prolly just needs to seat the rings. it might take 7-8k miles..
hanging throttle, prolly needs the max fuel screw backed out a touch. should take care of the smoke too..
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X2 Pending on the rings I've seen it take as long as 10K miles.. But also check the vacuum system.. Make sure there are no leaks.. The vac pump exhausts into the crankcase, if there is a leak and it's sucking extra air in, it'll be pumped into the crankcase...
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I keep forgetting how long diesels take to seat rings (Goetze rings, btw), but the amount of air coming out my valvecover seems almost a bit excessive. I've backed my fuel screw way down so I know it's not that (that was my first thought)... It's at least a 1/2 turn lower than it was and I'm still experiencing this issue a bit.
I've got my PCV system hooked up with 3/8" hose because that's what fits on my catch can barbs, and it's generating enough crank case pressure to push oil out the valvecover gasket... I suppose I'll just keep putting miles on her and see what happens.
I'll check the vacuum pump out, anywhere they're known for leaking that maybe I should check?
Car was at 362,000km when I re-ringed, just hit 365,000km today.
In other news I have an exhaust leak to fix in my flexpipe now too... :(
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If you are running synth oil drian and flush it with conventional. Then top it off with conventional oil and vary the RPM under load constantly while driving. Otherwise this maybe as good as it gets. I did mine and really didn't have any oil consumption or valve cover air after 300 miles with that approach. I think I lost 5 oz of oil during break in...I leaked a ton but didn't burn any.
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I'm using conventional oil, have been since I put the new rings in. I haven't done any steady state crusing with it since I rebuilt. I've broken in several motors in the past, this is just my first diesel rebuild. I don't think she's burning a whole lot of oil, mostly just pushing it out...
I refuse to accept "this is as good as it gets" though because it's not, nor is it acceptable. If I have to tear down and do it all over, I will. As things stand I'll give it a few thousand more km and see how it looks then, I suppose. There's no reason for this much crankcase pressure to be acceptable, I don't think it was this bad before the rebuild which substantiates that the rings aren't seated yet.... I'm just used to gassers that seat the rings in a few hundred km, I suppose.
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I meant as good as it gets with those rings. Diesels are a bit tougher to break in than a gas counter part. The battle is mostly over if you are not using syth. Make it work and it "should" seat all well.
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Does the air go away when you pull the arm on the pump? Sometimes it is all the cam and the way the overlap is at low RPM.
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Thats funny you said that. My AAZ when at idle blows a good amount of air out of the oil filler cap. WHen you pull the throttle off idle. It goes away, almost completely!
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It does seem to improve when I take it off idle, and after much musing and staring and scratching of heads this morning, we're going to hope it's just a ***ed valve cover gasket. I had no smoke at any RPM out the oil cap, and my PCV has oil where I expect it and not where I don't. I didn't realize the VW diesels pass as much air into the crank case as they do, confirmed that it's not an abnormal amount from my buddy's coworker that's been a VW tech since before these motors came out...
Right now I've got the valve cover resealed, and curing. I'm going to go out later and give it a try and hope I was just getting too concerned about nothing. I need a vacation from my life... I've got too much stress and it's causing me to over-think things...
Will report back this afternoon and see what's happening with it then.
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Keep Calm and carry on
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It does seem to improve when I take it off idle, and after much musing and staring and scratching of heads this morning, we're going to hope it's just a ***ed valve cover gasket. I had no smoke at any RPM out the oil cap, and my PCV has oil where I expect it and not where I don't. I didn't realize the VW diesels pass as much air into the crank case as they do, confirmed that it's not an abnormal amount from my buddy's coworker that's been a VW tech since before these motors came out...
Right now I've got the valve cover resealed, and curing. I'm going to go out later and give it a try and hope I was just getting too concerned about nothing. I need a vacation from my life... I've got too much stress and it's causing me to over-think things...
Will report back this afternoon and see what's happening with it then.
FWIW, i just fought with a leaky valve cover gasket.. i ended up replacing my VC, and gasket. went from stock diesel units, to an ABA v/c and gasket.. then it leaked. so i put some silicone on there too..
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Keep Calm and carry on
lol Thanks dude.
R.O.R. - Yeah I have some of the actual VW silicone gasket replacement on both sides of a new valvecover gasket, I don't expect any further issues. I'll see if it starts popping my dipstick out, or loading up my catch can... Then I'll worry.
I'll be taking it out for a healthy blast tonight, so if it's gonna leak or blowby, I'll find out tonight.
Spent all day fighting with sunroofs.
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Well I have no idea why it was continuing to smoke after I'd turned the fuel screw down, but with my resealed valve cover the hanging revs, gouts of black smoke a the wrong times, and oil puking all over my engine bay have all been resolved.... Mileage is through the roof right now too with the fuel screw so far back...
Feels good to have a motor with no oil leaks again/for now...