Blue-White smoke on start???
05-09-2002, 06:22 AM
#14
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Re: Do you mean Valve guide seals?
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Yes, same thing.
When you shut off your car, some of the oil will puddle around the valve stems (rather than draining back to the crankcase). If the valve stem seals are leaking, oil can sneak by the valve stems into the combustion chamber, onto the pistons. When you start the car after it's been sitting a while, the oil will burn in one puff of blue-white smoke.
Though annoying, normally this is not a major problem. I had a Saab with 150k miles on the clock with the same problem. That car used about 1 qt of oil per 3000 miles. If oil consumption does become excessive, replacing the valve stems seals should not be a mega$ job.
Yes, same thing.
When you shut off your car, some of the oil will puddle around the valve stems (rather than draining back to the crankcase). If the valve stem seals are leaking, oil can sneak by the valve stems into the combustion chamber, onto the pistons. When you start the car after it's been sitting a while, the oil will burn in one puff of blue-white smoke.
Though annoying, normally this is not a major problem. I had a Saab with 150k miles on the clock with the same problem. That car used about 1 qt of oil per 3000 miles. If oil consumption does become excessive, replacing the valve stems seals should not be a mega$ job.
05-09-2002, 06:40 AM
#15
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The turbos impeller rotates on a shaft. The shaft has bearings that are fed with oil for lubrication
The shaft needs seals to keep the oil "in place" and if they are worn,oil will leak out.If it leaks into the exhaust side of the turbo.....smoke. Valve guides have a seal(most of them) the seals the top of the guide and the valves stem as it passes through the guide. If they are worn oil will get into the combustion chamber and be burned.......smoke.I don't know about the turbo seals( I don't have one) but valve guide seals are more prone to cause excessive smoke on start-up because when the engine is off oil will pool around them in the cylinder head and seep into the cylinder. The longer it sits , more oil will accumulate in the cylinder .....more smoke on start-up.
05-09-2002, 07:58 AM
#19
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Say what?
are you talking about the Cat failing? how would an exhaust leak change the color of exhaust?
BTW, did you have an auto transmission die last year? I was looking for the posts but couldn't find them. What were the symptoms before it died?
BTW, did you have an auto transmission die last year? I was looking for the posts but couldn't find them. What were the symptoms before it died?