Railroadman

Started it up, then shut it down. Since we're not expecting a new pope, the white smoke out the tail pipes does not portend good news. And that sweet smell of coolant is unmistakable. Intake gasket? Cracked head? Worse?

Jitsu

sounds like head gasket. Is the engine oil milky?

Railroadman

Have not checked yet, going to take a better look soon.

Railroadman

I don't believe there is water in the oil. It does not look milky. I warmed up the car until the exhaust manifold was hot, used a screwdriver to drip a couple drops of water onto it and they immediately disappeared. Dropped a couple drops of oil off the dipstick and got a little smoke from the oil itself but no bubbling or spitting.

70 degrees outside so this isn't condensation, plus it has a strong aroma of almond or coolant. I'm thinking of re-torquing the intake to see whether it has loosened up. Obviously I'll have to take it off and put new gaskets on but I'm curious what the readings are as it sits now. Any other thoughts?.

EDIT - the water running down the driveway is unrelated to the car.

ls777z

Nothing like starting a holiday weekend on a high note...

mazdaverx7

Before condemning the head gaskets you may want to do a leak down or compression test. My 86 smokes a bit when you cold start it and let it idle for a few minutes the smoke is a grayish white and there's quite a bit of it. After a few minutes it goes away. Have you taken it out for a drive to see if its breaking up, has a loss of power or if the smoke goes away?

Railroadman

There is enough white "smoke" - steam actually - and very strong odor of coolant so I know something isn't right. Have not done a compression yet. It has been doing this slightly for a while, and has slowly been going through coolant. Yesterday was noticeably worse so I didn't try any long drives.

We'll be away the next couple days but I'll start getting on in Monday. Compression test might be a good place to start.

Railroadman

Finally going to get into this issue a week later than I had hoped. I'll have a compression tester but IIRC a few of the plugs on that thing are a royal PITA.

Trying to think of the logic - if the problem is a head gasket or cracked head, that likely would show up with a compression test, as a lower reading. But if it's an intake gasket issue, it's going to have nothing to so with the compression because the valves will still close tight. Am i right on that?

I just got a belated Christmas present of 2 nice new torque wrenches (Precision Instruments 3/8" and 1/2" drive split beams). So I'm going to go through the intake bolt pattern and see if any of them are showing less than proper torque, or if there is significant variation in any of them. Will report the results here in a day or so.

Any preferred brand of intake gasket for this thing? Last time I replaced them was 10 years and 21,000 miles ago so in theory they should have been good for way longer than that.

Thanks for input or suggestions.

mazdaverx7

If an intake manifold gasket is bad it will not affect compression test results.

Railroadman

Thanks - that was my thought but wanted a second opinion.

Weck86

FWIW, in my experience steam out the exhaust, coupled with coolant smell, is almost always a head gasket issue. My 86, a pace car convertible has aluminum heads and I had cracked heads which would also have the same symptoms as you. Sorry for the potentially bad news, but I think you have a head gasket issue.

Railroadman

Yeah, I know, but a guy can hope, can't he? The rear main seal is bad also and maybe the time has come for a serious project - as if I need another one! I have a '64 which has yet to see the road, and a '66 Chevy truck which has been under restoration longer than it was on the road!

Weck86

I hear ya. I've got a 73 EL Camino that has been on stands for two years. Haven't even fired the rebuilt engine yet, lol. Yesterday after a nice hour and a half ride in the 86 Vette, I decide to further trouble shoot the hunting at idle issue it has. So following the manual to set base idle: jumper a b at the ALDL, ignition on (not start) for 30 seconds, then disconnect IAC (plus disconnect distributor timing wire). Easy so far, right?

Now try to start, car must be in closed loop, and set base idle to 450 in neutral. So I try, car coughs and dies and bam I loose instrument illumination on the Atari dash and no power to starter, dead. I think maybe I heard a snap during all this. Great, I probably fired something, great. Checked battery and voltage is low, plus it's old, old, old, 9years. Guess I got good service from it. Anyway going to get new battery and cross my fingers. See, aren't old cars fun? Best of success with you Corvette repair.

Railroadman

Good luck with that! Hate to say it but IMHO if the problem was an old/low battery, it wouldn't come on all of a sudden like that. Altho at 9 years old it doesn't owe you anything. Seems like one thing always leads to another, but that's the fun of it (or at least that's what I keep telling myself! )

Railroadman

Gave up for today. The car is outside and we have had repeated cycles of sun, rain, sun, rain. Each time I get the tools out and start, I have to quit.

I did check 5 of the 12 intake bolts with a torque wrench. They seem to be at about 28 to 30 rather than the specified 35. It would seem a big variation would be more likely to cause a gasket problem rather than all (so far) the same. However 28 vs. 35 is 20% under spec so I'm not ready to abandon hope it's an intake gasket rather than a head gasket.

Family visit tomorrow so probably Monday before I resume as it stands now.

Renfield

Dead Chevys on the lawn are a staple of the South. Like sweet tea or grits. Guess it's true up North too.

Railroadman

The '64 Vette and the '66 truck are garaged. The '92 Vette sits outside, got it covered up because the damn maple tree is sending down its annual 10 million helicopter seed pods and I'd really rather not get them into every nook and cranny of the car.

Meantime the '05 F150 (200,000 miles) and the '11 Escape (95,000 miles) continue to roll up the miles.

Renfield

My '83 F-100 is the same way. LOL. You can't keep a straight six down. Gotta have wheels for when the Optispark sheets the bed.

I drive about an hour from the lake house to the city and I've often though of photographing the ubiquitous front lawn Chevy thing. I don't see Fords or Dodges. Just Chevy. It's usually a Camaro, followed closely in popularity by the El Camino. There's even a couple Caddies. One guy had a C4 for a short time. I gave him a wave once when I saw him with it. But he soon traded for a Camaro. It's on ramps.

Usually, the front is on ramps and the hood is off or partially open. And they NEVER move. It's coffee table book material.

Good luck with Stanley Steamer.

Railroadman

And in addition to the lawn ornaments, some will put out "bait". We have had more than one thread on C1-C2 about somebody who has a "63 split window rotting away in a yard, just for the fun of telling would-be buyers "no!" Sometimes the car is partly covered with a tarp, sometimes just barely sticking a fender out from behind a shed. Somebody will report the "find" on the forum, and somebody else will link a thread from 5 or 10 years ago on the same car, same place. The owners are just trolls who get off on fooling guys into thinking they might get lucky, then shooting them down. (the second chapter comes after said troll dies, and his heirs think they have a gold mine because hey - it's a '63 coupe and they are worth a lot! )

Tom400CFI

I hate to say this, but I don't think it's the intake. The LT1 intake is dry. There are no water ports in the head OR the intake...so the intake could be loose as a goose and still not leak coolant.




Even if there were water ports, the water would simply leak into the oil....not the combustion chamber.