Possible head gasket problem?

[z_ya]

I've got a 1978 280Z all stock and I've had a few people tell me that white smoke comes out of the exhaust. Well today I have seen it for myself. Is it my head gasket that has gone bad? It only does this when I get on it. And if so how hard is it to change the head gasket on the L28E.

Sorry if these are stupid questions, and thank you.

[madkaw]

Could be several things like head gasket or valve guides.

Is the car running good or the same as before you noticed the smoke?

How do the plugs look?

Is the car overheating?

You can always borrow a coolant pressure tester from autozone and do a pressure check on the system. The pressure should rise with a blown gasket.

[LeonV]

Compression test should be the first thing to do. Do that and report back.

[z_ya]

Alright guys I'll either do that tonight or tomorrow night and hopefully we can figure it out from there. Thanks

[grantf]

I second the compression test. I used this guide: http://atlanticz.ca/zclub/techtips/compressiontest/index.html

Also, are you loosing coolant?

Replacing the head gasket is not a simple task, but not rocket science. be prepared to also replace youre intake/exhaust manifold gasket, probably new manifold studs and new head bolts. You will disconnecting all of the EFI electrical connections so lable them, be systimaticle and take youre time using penetrating oil on all bolts and nuts.

[Captain Obvious]

You can always borrow a coolant pressure tester from autozone and do a pressure check on the system. The pressure should rise with a blown gasket.

The pressure in the cooling system will always rise as the engine warms up, regardless if there's a head gasket issue or not.

How do you differentiate between a normal rise and a head gasket caused rise?

[Wade Nelson]

A) Are you losing coolant?

Warm the engine up with the radiator cap off. If you've got major bubbles, you've got a leaking head gasket.

C) Romp on the gas with the cap off. If fluid comes spurting out of the radiator, you've got a leaking head gasket. Just a gentle rise / overflow is just the water pump pumping harder at higher rpm.

D) pull all six plugs. If one is immaculate, you've got a leaking head gasket.

E) Go to a COMPETENT shop and have them test your radiator fluid for combustion gasses. Note--- the reagent used

to do this goes stale sittign on the shelf. An incompetent shop will give you a bad reading. A competent shop will first TEST the fluid, using the mechanic's breath (which contains C02) which should trigger fresh reagent into changing colors. Which is, all in all, why I don't recommend this test.

F) put a pressure tester on it. If needle bounces with engine running, you've got a head gasket leak.

G) Let someone else drive your car. Follow them. If you see white smoke every time they get on it, and it's not coming from the tires, youv'e got a head gasket leak.

H) Smell your exhaust. Ethylene glycol, especially hot / vapors, has a very distinctive smell.

I) Just give up and accept the fact you ahve a head gasket failure.