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Old 08-20-2007, 01:03 PM   #1
72Blazerod
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Smoking during warm up?

Hi guys,

I'm about to put my 1972 Blazer back on the road after a 5 year hiatus. It still has the original 350 engine in it that has at least 123,000 mile (maybe 223,000 miles). It runs strong, but it used to smoke like H*@L when I would start it up cold. Once it warmed up, no smoke. I when I say smoke, I mean lots of it and for like 5-10 minutes until it was warmed up. It was a white-grey sort of smoke, not really very blue. The natural culprit would be the valve seals, which probably do need to be replaced. But would valve seals cause it to smoke for so long? I was wondering if it may have something to do with the carb (too rich maybe), or low compression in one of my cylinders (haven't done a compression check on it). The oil is not milky or grey, so I don't think there is water in it, and it doesn't smoke forever like it would with a blown head gasket or cracked block. It smoked so bad, my next door neighbour would come out and complain EVERY time I started it up (hence, it being off the road for 5 years).

Any ideas?

Thanks,

Rod
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Old 08-20-2007, 02:38 PM   #2
hgs_notes
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Re: Smoking during warm up?

The valve guides are probably worn pretty bad. That, along with bad seals will make it smoke pretty good. Sounds like it's time for a good valve job.
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Old 08-20-2007, 09:00 PM   #3
70gmcjimmy
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Re: Smoking during warm up?

What HGS_Notes said is right on in my opinion.

When the choke is shut, it causes a higher vacuum which will draw more oil thru worn valve guides. As the choke opens, smoke decreases. My Jimmy was doing the same thing when the engine was pulled at 153K.

Later---DAC
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