R32 Gtr Exhaust Smoke Issue

[trustr32]

Okay. I don't expect anyone to be able to diagnose the problem over the internet and I'm not even sure anyone will have seen this problem before but I have an R32 GTR that I've been having long standing issues with oil smoke from the exhaust.

The car has not been driven since rebuild.

I'll outline the history briefly so people know whats going on.

R32 GTR

Fully rebuilt engine about 14 months ago with 0kms on it. Car has not been driven at all since.

New 2860-5's

New stock position custom made stainless exhaust manifolds

Xforce dumps

2.5 - 3.25 inch stainless y-pipe

New 3.5 inch stainless 100cell high flow cat

3.5 inch straight through exhaust with cannon

New Custom 3 inch stainless intakes

New vent to atmo catch can with 20mm inlet/outlets

-I put the car back together and had oil smoke from the exhaust. Cleaned exhaust and noticed oil seeping from front turbo dump pipe. Pulled front turbo off sent back to be inspected checked out fine. Put car back together still smoking.

-Got 1mm restricted banjo bolts made. No change. Found very high oil pressure on idle (115psi) pulled engine out put new N1 oil pump with gears back on. Put engine back in oil pressure fixed so took in to get a run in tune. Mechanic rang me and said there was oil smoke on boost.

-Took car home. Checked 1mm restricted banjo bolts they turned out to be nearly 2mm. Made some actual 1mm ones no change.

-Put stock oil feed banjo bolts in and car smokes when revved past 2500rpm.

The car will not smoke all the way through warm up. I can leave it idling for 10 minutes without any smoke whatsoever but as soon as I give it some revs it will smoke oil smoke from the exhaust.

Now I pulled the y-pipe off this arvo to change the rear turbo oil drain because Stao from Hypergear suggested the right angle bends might be restricting the oil draining from the rear turbo causing it to seep out past the seal and before I changed the oil drain I decided to warm it up and see which turbo was smoking more front or rear.

Warmed the car up no smoke. Nothing unusual but when I gave it a few revs still no smoke. I let it warm right up and revved it up and down the rev range and there was not an ounce of oil smoke coming out of the dumps. A slight puff of carbon once I backed off but I could not get it to smoke.

Now I cant understand how just dropping the exhaust off would fix the problem but it's like chalk and cheese. With exhaust on it plumes fresh burnt oil smoke without the exhaust theres nothing.

Could the exhaust be causing too much back pressure or something causing the turbo shafts to shift forward allowing oil to weep past or something?

I'm sorry to ask everyone but I'm at the end of my patience this has been going on for over a year with no fix and no mechanic seems to be interested in troubleshooting they all just say turbo seals are f**ked.

ANY ideas will be welcomed.

Cheers Brodie

[blind_elk]

When you rebuilt the engine, did you also do the head, specifically valve stem seals?

[trustr32]

Yeah man full reco top and bottom. Just a basic build nothing expensive or over the top. just new parts/gaskets/bearings with forged rods/pistons. And hi octane sump extension.

Edited September 29, 2013 by trustr32

[trustr32]

So I thought I would start eliminating my exhaust piece by piece. I thought maybe the CAT was going to be causing the restriction so I put my y-pipe back on without the rest of the exhaust and BAM smokes back. It wasn't even on there long enough to heat the Y-pipe up. So I am absolutely stumped now I have no idea what is going wrong.

[portaz]

Sounds so similar to my problems , call scottym35 or rotomaster, rotomaster in Melbourne explained and inlet imbalance causing a slight movement of the shafts , maybe my guess is those shit x force dumps which never line up properly putting pressure on the housing which u don't see till y pipe is on thus causing the deformation to be more apparent?

Scott

[scotty nm35]

Did the old turbo's blow catastrophically? If so the exhaust is still full of oil and will take a few hot cycles to stop smoking.

[nammmy]

did it start smoking as soon as you started it after rebuild ?

how many hours of idling has the motor done in those 14 months. glazed bores ??

any warranty with the motor or did you do it you're self ?

dose it sound right when idling and at revs ?

Have you cleaned the inter-cooler out ?

[ZRBE]

This is probably really stupid and I am not mechanically minded lol...

Anyway.. Is your exhaust mounted properly, as in all the supports?

Maybe the weight of the exhaust is putting too much force onto something it's not supposed to up top?

Edited September 30, 2013 by ZRBE

[SiR_RB]

Could be burning old oil that was in the exhaust ?

Try not to idle a fresh engine for too long

[portaz]

Nah it's a long running issue he's had similar issues to me even though the setup is tried and tested we have both had nothing but problems, it has to be a balance issue I think if the y pipe being removed stops the problem ? I hope it's all soughted for us both soon I havnt seen my car in nearly 3 months either !

[trustr32]

Hey guys so exhaust has been cleaned. it did smoke as soon as engine went back in but that was from my original issue of a copy oil pump (didn't find out until I pulled the engine again) running at 115psi at idle.

I originally thought glazed bores too but that wouldn't explain how it smokes when the y-pipes back on and doesn't when its only out of the dumps.

I cleaned the cooler and every other pipe other than twin turbo pipe is new custom stuff.

Engine was built by pros they do mostly all the machining in the tassie scene and have built tons of RB's.

Engine runs like a dream idles beautifully revs crisply if it was registered id take it for a run at night so no one could see the smoke with the exhaust off you can hear both turbos spool down after a rev so everything is sweet other than god damn oil smoke.

I've got a couple of numbers of some people to ring and chat to but I'm also going to get hold of a set of steel wheeled stockers and swap them out so I can eliminate any actual engine problems hopefully and go from there.

[trustr32]

Hey guys so exhaust has been cleaned. it did smoke as soon as engine went back in but that was from my original issue of a copy oil pump (didn't find out until I pulled the engine again) running at 115psi at idle.

I originally thought glazed bores too but that wouldn't explain how it smokes when the y-pipes back on and doesn't when its only out of the dumps.

I cleaned the cooler and every other pipe other than twin turbo pipe is new custom stuff.

Engine was built by pros they do mostly all the machining in the tassie scene and have built tons of RB's.

Engine runs like a dream idles beautifully revs crisply if it was registered id take it for a run at night so no one could see the smoke with the exhaust off you can hear both turbos spool down after a rev so everything is sweet other than god damn oil smoke.

I've got a couple of numbers of some people to ring and chat to but I'm also going to get hold of a set of steel wheeled stockers and swap them out so I can eliminate any actual engine problems hopefully and go from there.

[scotty nm35]

Oil in the mufflers. There is no way to clean it out, it needs to be burned off on the dyno.

Or are you saying it burns oil with just the front pipe on the car?

[trustr32]

Just the front pipe man. No smoke when it's straight out the dumps but as soon as the y-pipe is on it smokes. I didn't let it run for ages when I put it back on as soon as I realized it was smoking I gave up but I don't remember it being as bad as when the full exhaust is on. I'll pull the y-pipe off and give it a super duper good clean up and try again just with that on to totally eliminate exhaust but I don't think it's that.

[scotty nm35]

I can't see how that small addition of back pressure would affect the oil seal in the rear of turbo, or anything else for that matter. Residual oil in the pipe is the most likely scenario. Let us know how it goes.

[trustr32]

Yeah neither can I but I'll give the pipe a clean and see how that affects things. if its an improvement I'll clean the rest of the exhaust back up and book in a day at the track to see if I can't burn the rest of it out.

[trustr32]

So I gave the Y-pipe a proper clean up. 3 cans of de-greaser and a home made scourer/bottle brush/pipe cleaner and I got it to about 98%. It probably had about 2-3mm of carbon/residual oil coating the inside. Put it on and got it upto temp gave it some rev's and there was a little bit of smoke but nothing on what it was like previously. I'll get the rest of the exhaust cleaned up in the next week or so and see how it goes but at the moment whilst I don't want to get my hopes right up there hopefully you were right Scott. I'm quietly confident that it may be a fix.

[portaz]

I'd put restrictors back in though as well if it were me

[trustr32]

I'd put restrictors back in though as well if it were me

Yeah man if the oil issue is fixed/greatly reduced with the exhaust cleaned then I'll put the restrictors back in and also put the GCG oil drains on then measure the oil flow just to make sure. I still think they will need them as my oil pressure (I put a gauge in the engine bay like you suggested) rises fairly rapidly with the rpm.

[portaz]

Wouldn't want to mess up that clean exhaust lol