My friend has a 1986 vette with 36k original miles. For the last year, it has been garaged and not run at all. We started it up a couple of days ago and 30 seconds later there was smoke coming from each side of the engine where the exhaust pipe connects to the stock manifold. It smelled like burning oil, but maybe more bitter. It wasn't a big cloud, just a steady stream from both sides. The car did not smoke when garaged a year ago. We ran it for about 5 to 10 minutes, smoke just became steady, but not a cloud or anything. Didn't seem to have any real "force" behind it, other than heat rising (not being blown from somewhere). The emissions tube (EGV?) is definitely not connected.

I checked the exhaust and it had smoke too, but when I held a peice of paper to the pipes, they didn't seem to be blowing any oil out and there was no discernable smell there.

Looking around the valve covers, couldnt really see any oil getting on the exhaust, but it's tough to see down in there.

I am considering buying this vette from him ($4K), but am concerned about needing to rebuild the engine if the rings have gone. There isn't much money in the budget for that.

Could you help me estimate what scenarios could be here and what the cost of repair would be (either by me or a mechanic if necessary).

Thanks very much,
Would love to have a vette and do some work on it, but not sink a ton of cash into it and never drive it.

 

Sounds like just dried up old valve cover gaskets. You really should try to duplicate the trouble and find out where it is coming from though. It might be valve seals also. Get her up on ramps and lots of good light. At 36,000 miles shouldn't be rings (unless the car has been abused or neglected). My 86 did this same thing when I received it at 130,000. Problem was old valve cover gaskets slow leaking oil on exhaust man. Replaced and good as new. If concerned about rings do a compression check.

 

Smoke always strikes terror in your heart when you see it. You instantly think doom. However, a car that smokes when it has been sitting awhile can come from a variety of places. Some are cheap fixes.

Was this the first time the car has been started in awhile, or is it doing this every time you start it?

If you get a chance to start it again, focus on the exhaust pipes. Initial smoke can come from worn valve guides. As the engine sits the oil drains down the stems of the valves into the cylinder. This is a nuisance, but really does not affect performance. There is a way of changing the valve guides without pulling the heads. If the heads come off, which you may want to do if there other leaks, you may want to do a valve job. But at the low milage, I doubt it would need it.

Billowing white smoke from the exhaust is water and can come from a bad head gasket or a cracked head or block.

Smoke at mid rpm range can be bad rings. The best way to see if its rings is drive the car and have someone follow you and see what happens when you get on it. The problem is that sometimes the only way to tell what the rings are doing is drive the car for awhile and see what the oil consumption is. There are compression and leak down tests that some mechanics can do as well.

As for smoke coming off the engine, the first place to look and see if the engine has oil on it is below the valve covers. Those are fairly inexpensive to fix.

Also, the intake manifold can leak oil. Mine did. It can drain down the front and back of the engine.

One final comment. I had to replace the intake manifold gasket due to oil leaks. It took days for the oil that had already leaked to make it down the side of my engine and quit dripping on the floor.

From what you have said so far I would be encouraged, but more testing is needed.

Glenn

 

Thanks for the replies so far.

The engine was not reved, this happened at idle only. This was the second attempt to start in 3 weeks. Same problem both time, but only run for 3 to 5 minutes first time and 5 to 10 next one.

The exhaust smoke was not white. Definitely had the burning oil smell (nbeen around a lot of my dad's GM junkers in the past)

The more I think about the rings, the less concerned I am. Low miles, smoke on both sides was equal amounts

What would make smoke gently flow from around the headers where they connect to the exhaust an equal amount on both sides? I think intake could be it, but the drip pattern doesn't seem to work out right. Valve covers, maybe, but both would be going bad, but still more likely.


Also, Is there any scenario that would keep me from wanting to drive this to a shop for inspection? oil level is fine, but oil looked kind of dirty brown.

 

If at all possible, I would change the oil. Check the coolant levels.

Then I would fire up the engine and let it run awhile. You would be amazed at what simply running an engine that has been sitting awhile can do to make it run better. Sticky rings can loosen up. Impurities can be burnt out.

I recently did this with a different type of car. It had not been run either. At first fire up it smoked from every possible place. But I let it warm up and run for about 20 minutes. Over time it started running better and better and smoked less and less. Did this several times during the day. Put some Rislone in it and ran it some more, changed the oil again and kept running it.
By the end of the day it ran fine. A tune up did the final trick.

In your case, with such low milage, you do want to make sure you don't hurt the engine, as a car with that low a milage is worth some money. If you have AAA you can tow it to a garage and let them take a look at it.

I would be encouraged by what you have told us so far. My guess it that it is a combination of leaks and simply needing to run some. Keep us updated.

 

If it is white smoke it is a coolant/water problem
If it is blue smoke it is an oil problem
If it is black smoke it is fuel problem

 

 

Did you ever let it run till it got good and hot.
Might cure some of the smoke issues.

 

My 84 used to do that. What I did was give the engine compartment a good degreasing and tightened down the valve cover bolts. I have not had it smoke from the exhaust since then. Could be an easy fix and sounds like a great deal!

 

The more I think about what I saw, the more I feel it's probably valve cover gaskets. it's really the only thing that could have dripped onto the exhaust. Probably did it for a while while parked and is just simply burning off now.

I'm going to get a flatbed out and have it towed to a place. Can anyone recommend a quality shop in the north of Atlanta area?

 

Do a compression test, and failing bad results, fork over the money. That's what many older Corvettes are often about.


*I* want to hear more about THAT!

RACE ON!!!

 

My '85 had leaking valve cover gaskets, did the same thing when they weren't tight. I replaced them, no problem.
If you have any doubts, make a $3000 - $3500 offer, then you'd have some money. See what he will accept.

Valve guide replacement with heads on engine?

I would love to have a 'Vette I didn't sink a ton of cash into! Just one...

 

I spoke in error about the valve guides.

It is the valve seals that can be replaced without pulling the heads.

A few years back I bought an 87. The engine was in great shape except it smoked at start up. It really bugged me, but I didn't want to go to the expense of pulling the heads. A friend of mine was a master mechanic at a dealership and claimed there was a way to change the valve seals on that engine without pulling the heads. I never did have him do it, but it involved using compressed air to keep the valves in the proper position. At the time, I looked it up on the internet and found some fairly detailed instructions on how to do it. I will try to find them and post.

Sorry for the terminology error

Glenn

 

Not to make fun of your friend or anything like that but this is general to the topic, but beware of certifications. I knew a dude that was a "ASE Certified Master Mechanic" at a dealership and he installed a set of brake pads backwards on my buddies old camaro. I seen it with my own eyes.

And most of everyone that works at Midas is ASE certified. Enough said.

 

Yes you can change the valve seals with heads on the car.

And to the topic..you said that a emmisions tube was off. That may be where the smoke is comming from. With a engine that sits over a period of time there will be smoke.
I think you should change the oil@filter and let it warm up. Then If there is oil thats burning it may burn off. Then you can see were an oil leak (if there is one) is coming from.
4,500 hudred is a very,very good price for a presentable vette.

 

Save your research time. Changing valve stem seals is common knowledge on this forum. Maybe you read about it here. If you do a search on this forum, I'm sure you'll find dozens of threads.

RACE ON!!!

 

Just talked with the local Chevy dealer where I dropped off my vette. They had two techs look it over.

Interior is a 9 out of 10.
Engine has leaking valve cover gaskets and oil pan gasket (the smoke)
Needs battery

And... the tranny needs some work...

The tranny problem could be bad, they couldn't tell without pulling it, but heard a pinging sound.

They estimate the cost of the tanny replacement to be around $2500 - $2700. I called a local trans repair shop and, sight unseen, they suggest a rebuild could be done for $700 - $900.

Any idea where I can get a good replacement auto tranny on the cheap?

 

if you can get a tranny rebuilt for $700-$900 then you have my attention!!!

Never ever ever ever...heard of that....not unless your pulling it out yourself maybe.

 

Marietta Transmission Service, in Marietta Georgia. (AKA "marietta transmission")

Very good shop. My dad used them for years and years.

It's there today so I'll let you know what the final bill is this week. Again today he stated a max of $900.00 for a rebuild. Also having them replace the rearseal while it's exposed. That's an extra $35.00 (incl labor)

 

Labor rates very so much around the country I think it's possible to in Georgia, and if your Dads used them a few times and has been satified, where can you get a better referal. I've had a couple done in Seattle, where I'm sure the labor rate is higher for around $1500. Good luck let us know and enjoy.