Compression Test Results with white smoke

[rutkak]

The car was running hot when I bought it. I swapped the radiator, thermostat and water pump. The water pump and / or thermostat ended up being the problem because I had to send the radiator back and by the time it arrived I was running a cool 185-195.

The hoses are good but I found the coolant leak...thermostat housing. I never noticed a leak there before because it's slight and the water probably evaporates by the time I check but it's definitely got a slight leak to it.

I'll keep an eye on it but in the next week or so I'll change the intake manifold gasket because there's a slight oil leak in the back. Once I swap it out I'll do another coolant pressure check and post the results.

Thank you Gentlemen, I sincerely appreciate your advice and help.

 

[69 Rustang]

I always considered blue smoke to be oil, white to be transmission fluid or coolant. You said white so I'd be looking at the trans modulator and possible coolant leaks.

 

[rutkak]

Looks like valve guide seals are next. I replaced the intake manifold gasket (oil leak in back) and am yielding the same white smoke. If the valve stem seals don't help then I'm on to the head gaskets. Interesting how there is only white smoke once the thermostat opens up though.

 

[72HCODE]

when the thermostat opens the engine has reached about 180-190 degrees for the coolant temperature. at that point if the engine block is cracked the joint would expand.

now it could also be a head gasket were it has a small leak and as the engine heats up the crack opens just enough to allow a little water in.

also by the time the thermo opens there is a pressure build up in the cooling system to 12-18 Psi. so when cold whatever leak there is would be closed off and there is normal air pressure in the cooling system

I'm betting as the engine warms up the smoke is present but not very visible. the PSI in the cooling system will be building up as the liquid and air inside expands.

same could be true for the valve stem seals as things heat up and expand leaks.

it is interesting when you work on your own car and you think back to when you took your car to a mechanic and the issue wasn't resolved in a timely fashion.

you can imagine the guy is like you trying to figure out what is wrong and throwing parts at the problem in the hopes it is something easy and cheap, meantime he is loosing profit and your aggravation level is going up.


i should also point out you could have 2 problems at the same time.

you could have a slight head gasket leak, and the valve stems seals are worn out.

the leak would not have been known had the valve stem seals kept the smoke inside the cylinders.

or it could just be the valve stems letting the exhaust gases leak into the valve covers and smoking out the vent.

it can drive you nuts.

 

[MotoArts]

Try this:

Take the car out for a brisk run, get it nice and toasty warm. Don't let it idle much when you get back.

Let it cool, and take out all of the spark plugs, KEEPING THEIR LOCATION RECORDED.

You should see an electrode/ground strap that is different than the other 7 (or possibly 6).

That plug should be cleaner than the others, as in steam cleaned.

That will indicate the cylinder(s) that is "burning" whatever is causing the white smoke.

I have found, in semi-severe coolant/head gasket leaks, that the plug may even have telltale wet green antifreeze on the electrode.

Do one check at a time, and only one check.

Isolate possibilities, don't compound them.

 

[Jeff73Mach1]

it is so much easier to just pull the heads and be done with it.

 

[marks73]

Magna flux.

 

[rutkak]

Jeff,

Roger that. It's certainly on the to do list but I'm moving in a week so I can't have my car inoperable (just in case) when the movers and car shippers show up.

I definitely think the heads are coming out. Once I get up to VA I'll see who has an engine stand and hoist for sale on Craigslist. Ideally I'll just pull the motor.

KR