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Smoking 89 S10 Blazer

This S10 has 4 wheel drive and the V6 engine and has 88,000 miles on it. Just about everything except the engine has been replaced because it was a work and plow car and took a beating. It is a great plow car, by the way. Recently a cloud of smoke comes out of the exhaust when you start the engine that has been sitting overnight. Mechanic says it is just old, but someone said that replacing the umbrella seals might do the trick. Stopped at my local auto parts store and they had never heard of umbrella seals. Any thoughts. CGA

I’m sure that “someone” was using slang for valve stem seals. Smoke at start up is a common sign of bad ones. Your “mechanic” is also right - though more vague about it. But if “just old” was as far as s/he got with it I might think about using someone else.

Unless you’re someone who will do engine work you won’t be picking these up at the local parts store and installing them.

There was an umbrella seal available for Chrevrolet engines for several years. They were actually boots that covered most of the valve spring and were somewhat effective to reduce smoke at start up but at a terrible cost. The seals kept the valve stems from getting adequate lubrication and after a few thousand miles of seeing a reduction in smoke at start up the valves would begin to wear so badly that they would not seat resulting is loss of compression. I installed several sets years ago and faced the results later. I would strongly advise not to install the seals. I doubt they are still available though. It might be worthwhile to remove the valve covers and check for sludge plugging the drains. Oil pooling on the heads might be the problem.

I agree with Rod. I also bought a set of these umbrella seals and installed them in my 350 engine in my truck. It cured the smoke at startup but wore out the valves and valve guides. Check for proper oil draining as this is a problem in the Chevy V6 and V8 engines.

thanks for the info. Would an oil additive do any good as I am tapped out on mechanics fees right now?

Other than cleaning out the oil return paths as suggested by Rod, I too would be inclined to just monitor the oil level and accept the puffs of smoke. And while I don’t recommend additives, and doubt that they’de reduce the leakage past the valves stem seals, it couldn’t hurt to try one. Their true function in life is to squeeze some extra mileage out of old beaters. Might help, might not.

If the heads are badly sludged up scraping the valve covers clean and changing the oil more often than usual, say every 2,000 mile would probably be a great benefit. A good detergent booster might be worthwhile but keeping the oil clean is foremost on the agenda. I long ago acquired a Plymouth for $100 that was consuming a quart of oil every 200+/- miles. I found the valve covers totally packed with sludge and the PCV system plugged with sludge. After scraping out the covers and changing the oil it was black in less than 100 miles so I changed it. After a few changes the consumption dropped, the smoke cleared up and I drove the car for a couple of years and sold it for $800. The only repair that I can recall was U-joints.

I am carrying a printed copy of your comments and suggestions around with me so when I get to the mechanic I can just read to him instead of trying to remember. I am using synthetic oil now so should I (88,000 miles) change the oil more often than every 3,000 miles. When my son is around the car gets many miles put on it, but he is about to go off to college so the blazer will sit around much more. thanks again. C