Author Topic: smoke??  (Read 3544 times)

Offline smoke

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smoke??
« on: February 12, 2008, 08:08:52 pm »
just bought a 85 gmc short box 4wd.guy said it started blowing white smoke.like it had a bad head gasket.so he shut it down and pulled it home.never fired it back up.my question is.would there be anything else to make it smoke like that?don't have any water in oil.but still might have a bad hg.when i took the air cleaner off it still had a thick metal screen thing same shape as the air filter and is was pretty dirty.like crusty dirty.just hate to pull it all down and find out it was from something else like maybe poor maintenance.hoping for the best.thanks for any input

Offline Leevon

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Re: smoke??
« Reply #1 on: February 12, 2008, 08:20:07 pm »
Valve stem seals will leak down when the get old and allow oil to enter the chamber which is why you see the white smoke at start up.  Cheap but messy fix. 
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1987 Silverado
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Offline VileZambonie

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Re: smoke??
« Reply #2 on: February 12, 2008, 08:25:21 pm »
Engine oil smoke isn't white it will bur bluish grey. The only thing that will burn white would be automatic transmission oil or coolant. A popped vacuum modulator diaphragm can draw ATF into the intake depending on which trans you have. If it's so equipped,pop the hose off of the modulator and check for the presence of fluid. If you suspect it's coolant remove the radiator cap and check the coolant level (cold of course) Is it using coolant?
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74 GMC, 75 K5, 84 GMC, 85 K20, 86 k20, 79 K10

Offline smoke

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Re: smoke??
« Reply #3 on: February 12, 2008, 08:53:05 pm »
has a 700r4.where would they vacuum mod be?not sure on the antifreeze.will check it tomorrow.

Offline VileZambonie

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Re: smoke??
« Reply #4 on: February 12, 2008, 09:15:05 pm »
No modulator on the 700R4.

open the radiator and check it. Top it off, run it with the radiator cap off, see what happens
,                           ___ 
                         /  _ _ _\_
              ⌠ŻŻŻŻŻ'   [☼===☼]
              `()_);-;()_)--o--)_)

74 GMC, 75 K5, 84 GMC, 85 K20, 86 k20, 79 K10

Offline smoke

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Re: smoke??
« Reply #5 on: February 12, 2008, 10:01:31 pm »
k will do it tomorrow and report back.thanks for the help