1JZ oil smoke question

destrux

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May 19, 2010
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For those of you that have had your stock twin turbos start smoking, when you pulled them off was there wet oil visible in the turbine outlets in the exhaust? My car went from smoking a little to smoking ALOT in just a few days. When I pulled the downpipe to check for signs of oil leaking into in the turbine outlets, I saw none. Just black dry soot. Also checked the intercooler piping.. completely oil free. Yet the car blows out large clouds of blue smoke constantly. Is the exhaust heat causing the leaking oil to burn off completely into smoke (leaving no wet oil laying behind), or are my turbos probably fine?


My dad is insisting it's valve stem seals, but I would expect those to cause a big puff of cold startup smoke and mostly smoke on decel. Unless maybe one completely cracked up.

Also, good compression test results (175 in all) and no wet oil on the plugs, and the car runs fine (the few miles I drove it after the bad smoking started).

I'd love to swap to a single.. I just don't want to unless I have to.
 
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hvyman

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Apr 17, 2007
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Do you have a new 1jz or a old 1jz? There is a tsb for the pcv valve. can pull something off the intake and take a peep inside.

Check for play in the turbos. If there is none then there prolly fine.
 

mkiiichip

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Sep 10, 2007
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Valve guide seals smoke on first startup, if there is none then they can be eliminated.

You can see there is oil in the turbine housing right. And there is none in the exh manifolds before the turbo (<guessing). History says these turbos smoke. So that only leaves one thing.

<this guy is in the same boat.
 

destrux

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May 19, 2010
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It's the old style, but I checked the PCV valve and it's working fine. I never got around to doing the 2JZ valve update on it yet, but I did disconned it from the valve cover and after running for 20 mins it still smoked.

I will check for shaft play though, I'll have to pull the inlet pipes tomorrow and take a look.

That's the thing... I don't see any oil leaking anywhere in the turbos. I didn't pull them off and take the housings off, but if it was smoking this bad I thought it would be visible just looking in from where the downpipe connects.

I ordered a set of valve stem seals... since I don't have money to replace bad turbos now anyway I'll just put those in for now. The engine has at least 100K on it anyway, so they're probably going to leak soon if they aren't now.
 

hvyman

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Valve stem seals normally will only leak when the engine is cold, when they start getting really bad smoke on idle all the time and when there toast smoke all the time.
 

destrux

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May 19, 2010
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I assume, but I'm not sure, I just did the swap 6 months ago, the engine still had the stock water pump which just failed (usually they last about 100-150K), so that's the mileage I'm guessing it has on it). It didn't look like the valve covers were ever off before I changed the gaskets during the swap.
 

kelson

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Apr 17, 2009
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If your 1j is smoking because oil is leaking out the hot side of your turbo into the turbine housing and exhaust, then the smoke is from the oil burning on the hot exhaust. So the smoke would only start once the engine has been running awhile and if you check in the exhaust you shouldn't see any oil since its being burned in the exhaust. make sense?
 

destrux

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Yeah, that's what I was thinking of too, and if the valve seals don't fix it that's what it's got to be.
 

kelson

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valve seals are kinda a big job. I would go find a hill and coast down it while in gear then get on the gas at the bottom. if you see a puff of smoke at the bottom its probably valve seals. because it came on so suddenly I would bet its one of the turbos. valve seals don't generally get really bad over the course of a week. I'm dealing with the same thing, I've been driving my 1j swap for about a year and a half and my turbos just started smoking like crazy. I'm going to rebuild them just cuz its cheep.
 

f00g00

Supramania Contributor
Jul 2, 2007
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You going to do the work yourself? Pulling the cams and shims and using compressed air to hold the valves in place while changing the seals?
 

destrux

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May 19, 2010
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I don't mind the time doing the job... I have nothing better to do tonight anyway. I've been working on cars for years, so I'm pretty quick doing jobs like this. I think I can get it done in 6 hours after work tonight. Doing my leaking cam seals too.

I'm not sure if I'm going to use rope or air to hold the valves though. Kind of leaning towards air because the rope method was a pain on the last engine I used it on (although, that was a V6, maybe it's easier on an inline). My thought is if the piston is at TDC and the valve pops open , loses air pressure, and drops down, I don't think the valve can drop too far, because the piston is right there. There should be enough stem sticking up out of the top of the valve guide to get it with a magnet or needle nose and pull it back up. If anyone knows otherwise, let me know.

Hey, I heard that the stock CT12A turbos are balanced on the compressor nut, and if you rebuild them you have to rebalance them because the nut gets replaced and throws the balance off. Are you having yours rebuilt or just doing it yourself? I was going to rebuild mine myself if I had to. I've rebuilt non-ceramic turbos before, just unsure if the ceramic wheels require any special procedures (other than being really careful with them). I saw rebuild kits on ebay for less than $100 each.
 

f00g00

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There is a tool here that would make the job easier.
Http://toyotool.com
I bought a used set of twins from Jose at kaizen and sent them to gpop shop to upgrade to steel wheels, I believe they show the kit online. Its a good thing I swapped them cause the rear one had half the blades broken.
 

destrux

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May 19, 2010
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Exhaust stem seals were toasted... they just about came off the guides by themselves. Intake were not far behind. Halfway done now, started at 6pm. Should finish by midnight.

Edit: They DID come off by themselves on both exhaust valves on cylinder 3. That explains the sudden increase in smoke. Good thing I didn't run it for too long after, the seals were banging up and down between the retainer and the top of the guide, the little springs fell off and were on my drain plug magnet. That makes me realize... if I would have done an oil change a few days later than I did I would have seen them and known immediately what was wrong. :: facepalm ::

That tool would have made it alot easier too.. I'm using a rail type tool that bolts to the cam cap holes and levers down on the retainers. It gets them off super easy, but putting the keepers back in is a PITA.
 
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destrux

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Haha... just to spite me it started smoking again almost as bad as before.

Going to start it (cold engine) and shut it off after a few seconds... and repeat 3X with some time in between so the turbos don't heat up. Hopefully that will make the oil leak visible in the exhaust without the oil burning off before I can see it. I want to know exactly where it's leaking. If it's not the turbine seals leaking, then maybe I screwed up a valve stem seal, or the motor has issues.

Edit: Hey... a great way to tell the turbo is bad is if you can hear the shaft physically slamming back and forth when you snap the throttle on and off. Every time I leave off the throttle after a quick rev you hear a loud "click" from the rear turbo. It has axial shaft play, about 1mm worth, I couldn't feel it before because it's such a bitch to get my hands in there to check it. Lets hope this is the source of the smoke.
 
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Dylan JZ

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Oct 18, 2007
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I had the EXACT same symptoms, and it was the twins.. no oil in the downpipe, catchcan, or intercooler piping.

also, sound is a great indicator, as said above. My rear twin started to whine on hot starts after a while, so that's was another easy giveaway.
 

destrux

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May 19, 2010
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Yeah I guess I forgot to update this.

It was the rear turbo. Once it was off I took the turbine housing off the center section and there was oil leaking out behind the turbine wheel.

The valve stem seals were definitely bad though, if I would have done the turbo first it would have still been smoking from the valve seals. So they had to be done anyway.

There's a bunch of write-ups on the VSS online, I used one for a 2JZ engine since it's the same procedure (it even uses the same seals).

I ended up swapping to a single turbo setup.