Engine Oil Stop Leak additives

[1981]

My 1981 is using way too much oil these days.
It is a daily driver.
All stock rebuilt engine.
Symptoms:
---> Does not leave oil on the ground.
---> Only blows white smoke during some start ups, if the engine was just run, then no smoke appears. The smoke is always present if the Vette sits overnight (about 12 hours). The smoke is like a big puff of cigarette smoke. No continuous smoking, this is not condensation, oil is being used.
---> Uses approx. 1 quart for every 200-300 miles.
---> Engine was rebuilt about 3 years ago (approx. 3,500 miles)
---> Was kept in storage during winters (approx. 6 months at a time) before I bought it.
---> Other than this the Vette runs great.

I do not know much about engines, but I would say that the valve stem seals are bad. Probably from sitting up in storage during winter months.

What do ya'll think would cause this problem?
Has anyone had this problem? If so, what would you recommend I do to fix it? Should it be a major worry right now, or do I have time before it "has to be fixed now".

Are there any Engine Oil Stop Leak additives that can be safely used without damaging the engine? I was recommended to use "K&W" to hopefully retore the seals. I really do not see how anything other than replacing seals could fix the problem with bad seals. So if this did not work I was going to then worry about the seals and replace them.
What do you think about this? Anyone ever used this stuff?

Thanks for the knowledge,
1981

 

[cntrhub]

Forget about the "Snake Oil." You hit it on the nail. You have dried out valve stem seals. No additive will help solve this problem.
You need an air compressor. A spark plug adapter, and a special valve compressor tool to change out the seals. The nice part about this job is, you don't have to pull the heads to do this. You need two packages of valve seals. The intake valve calls for one, but you are going to put a second set on the exhaust side. It works......for awhile. If you have worn guides, then nothing but a new set of guides, valves, and cut seats would be the next plan.
The spark plug adapter and compressor, will keep a constant flow of air inside the cylinder chamber to keep the valve pushed against the seat as you remove the spring, keepers, etc. from the head. There is a special plastic protective cover that slips over the valve's stem, so you won't cut the new seal. Make sure you push that seal "home." The final O-ring is set in place and then you are ready to reinstall the springs, keepers, etc.
The next step is to reinstall the push rods and adjust them. If you want help with that, just keep this same thread going...i'll walk you through with the adjustments.

 

[Yoda]

1981 I agree with cntrhub about the valve seals you state "using a quart of oil every 200-300 miles.." for peace of mind I think I would have a compression test done too.

 

[1981]

Thanks for the advice on the "snake oil". It's not going into the engine. I have never worked on an engine so the work will have to be done by a mechanic. The only problem I have is there are no local mechanics that I trust. Every car I have ever owned when put into the shop came back fixed but then started having problems somewhere else. $300 here, $475 there, $180 here, another $950 there. I would hate for this to happen to my corvette. It runs excellent, I am only having this smoke problem.

This weekend I went to a soccer tournament out of town with my daughter. We took the Vette and met up with a lady on the highway in her silver C5, she must have been about 70 years old. We waved to each other and she followed me in the traffic for about 45 minutes, rode up on the side of me, waved Bye, then exited at the next exit. First time I ever got a response from a C5! Not knocking the C5 community, but out of the 5 or so I see on a daily basis where I live, none ever wave back. They just drive on. oh well, I'll keep waving.

Well back to my oil problem, while on the highway I had to stand on it a few times to get around some people who felt it was better to drive 45 in the fast lane and create a wall of cars wherver they went. Looking in the rearview mirror I noticed everytime I did this smoke poured out of the exhaust for a couple of seconds! What does this add to my problem? or does this just confirm replacing the valve stem seals?

What should I expect to pay a mechanic for such work, and what should I look for to make sure the job is done without creating more damage to the engine? i.e. "Well the startup smoke is gone, but now it blows Blue smoke all the time." or worse "Now I leave oil on the ground everywhere I park".

Thanks for your knowledge again,
1981

 

[dmkoger]

My suggestion it to network with other Vette owners in your area. Doesnt matter if theyre c3, c5, or whatever. Just talk to them and find out where they take their vehicles. You also check with the Better Business Bureau for complaints.

 

[cntrhub]

Here's the take on oil smoke out of the exhaust pipe:
VALVE SEALS/GUIDES = Smoke on start-up. Smoke puffs, when lifting off throttle and applying throttle again...passing situtation. Common when lifting off the gas on down hills, and then reapply throttle... a puff of smoke will occur.
Smoke is therefore... intermittent...(but still burning oil slowly). Minor overhaul needed.
PISTON/RING = Smoke on start-up, continues at idle, and driving. Smoke noticeable from breather hose, dip-stick tube, and wet at the exhaust pipe's tip.
Smoke is therefore... constant. Major overhaul needed.