Blow back - white smoke

JOEGARCIA

MEMBER
1985 GMC SIERRA

I am getting blow back on passenger side of my 1985 GMC Sierra pu trk. From breather tube into carburator, it's white smoke. Even after I shut the trk off. But it's not coming out the tailpipe. It still has good oil pressure. Can you help me?( Oh, the engine came from a 1987 pontiac firebird)

Tuesday, April 5th, 2011 AT 4:08 PM

3 Replies

JDL

MECHANIC
16,098 POSTS

What about crankcase ventilation? If you remove crankcase oil fill cap, warm engine running, anything coming out? Are you losing coolant?

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Tuesday, April 5th, 2011 AT 7:16 PM

JOEGARCIA

MEMBER
3 POSTS

I pulled the oil cap off and yes it was smoking. Also, it idled up when I did and when I put the cap back on it idled down, running smooth. If it is losing coolant, could it be I need a new radiator? Also, I pulled the distibutor cap off and the coil i
s all rusty. Could that be part of the problem? I appreciate your help! Thanks, joegarcia

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Wednesday, April 6th, 2011 AT 1:35 AM

JDL

MECHANIC
16,098 POSTS

Blowby sounds like rings to me. If your losing coolant, check for an external leak. Does the oil have coolant in it?

You may need to check compression.

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Wednesday, April 6th, 2011 AT 3:10 PM