Occasional white smoke, need help!

[rickl750]

Hi Guys,

I have a stock 1978 280Z with 140,000 miles and I thought I had blown a head gasket a couple of weeks ago, there where large amount of white smoke coming out the exhaust. Anyway, I parked the Z until the head gasket came in, I then stated the car to work on and and it was back to normal no white smoke, it ran find for about a week and the smoke started again. This happens without rime or reason, it can happen first thing in the morning when I start the car for the first time or after driving it for a while. One day or two it's fine then on the third or fourth day it smokes, it's very inconsistent and I would hate to take the engine apart and find out it was something else than the head gasket. Any thoughts on this problem?

thank you,

Rick

[Mat M]

Did you not have the deck (block) and head checked for straightness? Did you overheat before this occured? What can you tell us that might point to WHY the gasket blew? Do you have pics of the original gasket?

If it is a blown headgasket, and there is a problem with the head/block tolerance, you will have blown gaskets from here to eternity without solving the core issue.

[sblake01]

This is just a shot in the dark but I thought I'd throw it in because it once happened to me. Is you car, by any chance, an automatic transmission? If not, everything I'm going to say can be disregarded. I once had an RX7 with an AT, and the vacuum diapraghm developed an internal leak. Since it works off of vacuum, it was pulling the slightest bit of ATF into the intake and causing the car to blow white smoke. It was an easy part to change, didn't cost much but I have no idea if the 280Z auto trans is set up the same.

EDIT: Never mind. I just looked at one of you other posts and I see that yours is a 4 speed.

Edited August 27, 2008 by sblake01
irrelevant info

[Mr Camouflage]

Could be valve stem seals. They will smoke on deceleration or after idling for a time if they are worn. I also read somewhere that someone had a problem with the brake booster. The engine was sucking in brake fluid through the brake vacuum pipe somehow (or maybe that was the AT that Stephen was talking about. Cant remember, was a long time ago that I read it). Something else to check before tearing the engine apart.

Do a compression test.

Edited August 27, 2008 by Mr Camouflage