Another Smoking Story

[mikemerkury]

Will try to do this short, 73 240z/Stock L28 from 280z/Dual Webber

Engine was suppose to have been totally rebuilt (top/bottom) 3 years ago. Always smoked a little under my ownership (2 years). Smoke is now out of control and i am ashamed of driving it. From cold start to normal running temp, SMOKE SMOKE SMOKE !!!. Any opinions, rings, valve seats, guides ? How much to fix this ?

[EScanlon]

You might finish the sequence of events.

Does it stop smoking once it reaches normal operating temp, or does it do it ONLY when you first start the car and not later in the day after you've run it and then parked it for a while. Does it do it always when you start the car any time during the day regardless of whether you ran it that day.

It's hard to tell the "color" of that smoke, is it plain old white or does it have a bluish tint to it, either one points to a different type of problem.

Have you checked your coolant levels, are they rock steady and not slowly gonig down? How about oil? Does it use "a little" or "a quart per tank of gas". When was the last time you took it out and gave it a good old spirited run on the highway?

I'm only parroting what I've read here, the other guys who are the engine mechanic type will undoubtedly have tons of questions, but you might start by answering the questions I've posed.

E

[mikemerkury]

You might finish the sequence of events.

Does it stop smoking once it reaches normal operating temp, or does it do it ONLY when you first start the car and not later in the day after you've run it and then parked it for a while. Does it do it always when you start the car any time during the day regardless of whether you ran it that day.

It's hard to tell the "color" of that smoke, is it plain old white or does it have a bluish tint to it, either one points to a different type of problem.

Have you checked your coolant levels, are they rock steady and not slowly gonig down? How about oil? Does it use "a little" or "a quart per tank of gas". When was the last time you took it out and gave it a good old spirited run on the highway?

I'm only parroting what I've read here, the other guys who are the engine mechanic type will undoubtedly have tons of questions, but you might start by answering the questions I've posed.

E

- After reaching running temp, it will stop smoking if i let it park for a while (5 to 10 minutes)

- Smoke is a bit "bluish"

- Coolant levels are normal

- Use a little bit of oil

- Gave it a "spirited run" on the highway last night. Problem have worsened on first start today.

[tlorber]

Have you tested compression yet? I think you need to do a leak down test to see where the oil is leaking from. It is either rings, valves, or valve guide seals.

[Zforce]

I vote valve guide seals, even if the motor was rebuilt the seals were probably dry rotted to begin with. And you didn't say the engine was fouling plugs so the valve guide seals are probably hard as little rocks. If you do it yourself with the proper tools (kd tools 3087) it will cost about 60 bucks, or you can pay a mechanic 300.either way it's the least expensive probable solution.