Smoky exhaust with a little clear liquid and sometimes black spots at startup?
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Smoky exhaust with a little clear liquid and sometimes black spots at startup?
Title pretty much explains it all. I've got a 91 pickup that, on cold startup and sometimes warm startup pushes with smoke out of the exhaust pipe, along with little droplets of clear liquid. The other day it also was spitting out little black specks. From what I've heard, this is a symptom of leaky valves and a bit of oil is getting burned?
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valve stem seals when leaking will burn off a little oil on a cold start. If your motor in fact has 275K this could be the problem or maybe a little oil is making it past the rings.
Does it leak oil at all?
Does it leak oil at all?
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There is some evidence of oil leakage around the front of the engine, some accumulation below the cylinder head and a little accumulation down on the shield below the radiator fan. Also, it does use oil faster than it should. I've been putting 20w50 in it, which several people have recommended based on its supposed ability to help 'plug' up any leaks.
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It's actually got around 282K now. I definitely plan to run it till it dies. I'm just hoping that doesn't happen for another 20000 or so. Keeping my fingers every day. Perhaps I should just have someone do a compression/leakdown test and get a better idea of what's going on in there?
#9
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motors will have condensation in the exhaust from the heating and cooling cycle. this will put out a white cloud of exhaust that can carry out pieces of carbon and can leave some water spots. it should clear up fairly quick depend on the temp.
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The clear liquid is probably water (condensation), which is normal (water is a by product of normal combustion). It should clear up after a minute, once the exhaust warms up enough to stop condensing the vapor.
Smoke, on the other hand, is not normal. If it clears up quickly after starting, as others have said I would suspect valve seals.
Smoke, on the other hand, is not normal. If it clears up quickly after starting, as others have said I would suspect valve seals.
#14
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normal, my rebuilt does this when it's cold out. The little black specs are from normal carbon build up getting wet from the condensation and being thrown out the exhaust. Smoke will happen shortly after startup once the exhaust pipe heats up enough to boil whatever condensation is left. Remember condensation builds up in more places than just the exhaust pipes, it will also build up on the inside of the intake manifold, inside the rocker cover, etc etc. Once the engine is started that water will make it's way into the cyls as well and be burned off as well leading to some smoke as well.
Also remember an engine always runs a little richer until the motor warms up and goes into closed loop. Carb'd motors are real prone to this, especially the carbon build up in the exhaust. Due to the fact, they typically run richer than an efi would when cold. But efi will do it as well.
As long as the smoke and water goes away after a little bit of driving etc etc, I wouldn't worry about it. Now if your truck does this when it's like 80 degrees outside, it might be a different story.
Also remember an engine always runs a little richer until the motor warms up and goes into closed loop. Carb'd motors are real prone to this, especially the carbon build up in the exhaust. Due to the fact, they typically run richer than an efi would when cold. But efi will do it as well.
As long as the smoke and water goes away after a little bit of driving etc etc, I wouldn't worry about it. Now if your truck does this when it's like 80 degrees outside, it might be a different story.
Last edited by xxxtreme22r; 11-19-2010 at 11:05 AM.
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