Oil smoke on startup - turbos or engine seals?
08-23-04, 07:20 AM
#26
It's the e-shaft mod... normally there's a thermal pellet that prevents smoky startups (likely for emission purposes) by not oiling the e-shaft right at startup... KDR mods this so that it oils it right away. That's a layman's summary, but that's the long and short of it.
Originally Posted by RonKMiller
I go with the Redrotor 1's turbos slowly going bad theory. And here's why:
I bought mine new, and I assure you it NEVER smoked on startup. At 75K on bone cold startup I get a little bit of smoke for a second or two, on warm startup none, nadda, zilch. The colder it is the more smoke I get - I park my car in a heated garage 99% of the time, but once in a while it is parked outside in 20 degree temperature. More smoke on startup. It ain't coming from the engine since I am pulling 18 inches of vacuum on a certificated vacuum gauge.
I attribute this to the warmer seals expanding and "sealing" better. That's why I am such an advocate of at least a 15 minute driving warm up before boost, in order to "heat soak" the entire engine and components. Thermal shock in extreme circumstances (as in airplanes) can sieze an engine.
I am definitely going with the RZ spec tubos when it is time, I like the abraidable seals idea.
I bought mine new, and I assure you it NEVER smoked on startup. At 75K on bone cold startup I get a little bit of smoke for a second or two, on warm startup none, nadda, zilch. The colder it is the more smoke I get - I park my car in a heated garage 99% of the time, but once in a while it is parked outside in 20 degree temperature. More smoke on startup. It ain't coming from the engine since I am pulling 18 inches of vacuum on a certificated vacuum gauge.
I attribute this to the warmer seals expanding and "sealing" better. That's why I am such an advocate of at least a 15 minute driving warm up before boost, in order to "heat soak" the entire engine and components. Thermal shock in extreme circumstances (as in airplanes) can sieze an engine.
I am definitely going with the RZ spec tubos when it is time, I like the abraidable seals idea.
08-23-04, 07:39 AM
#27
Perpetual Rebuilder
Mine does this and I have a theory about it so I thought I'd put it up here and see if other with the same problem see the same thing.
Along with this common problem I also have another common problem of gassy smelling oil.
So my theory is that my side seals are not sealing as well as they need to and during startup they are letting oil in the chamber until they warm up. Then even when warm under boost (run my single at 14psi) I get some blowby on the side seals which gets fuel vapor into the oil. Over time this fuel vapor thins the oil which allows more of it to get by on the cold start causing more smoke on startup.
Things I have seen to support this theory. No oil in my IC/piping. Smoke on startup doesnt seem to be temperature related (other than a completely cold start - I get none on a warm start) or have anything to do with how hard I drove the car the time before. There is fuel in my oil (only way those two can associate is at side seals). And it seems to be less of a problem with a new oil change (oil is not diluted and doesnt pass side seals as easy). My vacuum levels are always 1or2 inHg better after oil change. I have changed my oil yesterday so I will let everyone know what I see this morning.
I also always have a full oil resevoir. I think this can be accounted by the fuel being added to oil accounting for the extra volume of the oil that is lost.
Well are you guys that are having this problem smelling fuel in your oil? Notice any difference with a new oil change?
Oh and I have a factory reman with a t04S on it.
Along with this common problem I also have another common problem of gassy smelling oil.
So my theory is that my side seals are not sealing as well as they need to and during startup they are letting oil in the chamber until they warm up. Then even when warm under boost (run my single at 14psi) I get some blowby on the side seals which gets fuel vapor into the oil. Over time this fuel vapor thins the oil which allows more of it to get by on the cold start causing more smoke on startup.
Things I have seen to support this theory. No oil in my IC/piping. Smoke on startup doesnt seem to be temperature related (other than a completely cold start - I get none on a warm start) or have anything to do with how hard I drove the car the time before. There is fuel in my oil (only way those two can associate is at side seals). And it seems to be less of a problem with a new oil change (oil is not diluted and doesnt pass side seals as easy). My vacuum levels are always 1or2 inHg better after oil change. I have changed my oil yesterday so I will let everyone know what I see this morning.
I also always have a full oil resevoir. I think this can be accounted by the fuel being added to oil accounting for the extra volume of the oil that is lost.
Well are you guys that are having this problem smelling fuel in your oil? Notice any difference with a new oil change?
Oh and I have a factory reman with a t04S on it.
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trickster
2nd Generation Specific (1986-1992)
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07-01-23 04:40 PM
