black smoke

[johnd]

what would that be it is only there for about the first minute or so after start up I was thinking to rich or something of that nature but I am not sure...

 

[Ken]

Black smoke usually does indicate an overly-rich condition, however, on an older small block a wisp of bluish-white smoke will appear upon start-up due to leaking valve stem seals. It's a common enough occurence that it happened on the cars when they were new. The seal has since been redesigned.

A small amount of black smoke may simply be due to the rich condition imposed by the computer for cold starts.

Damn, I didn't even realize that I had wandered into the Shark pool. :eek

That's alright though, it's still a computer-controlled carburetor isn't it? :L

 

[AUSSIEVETTEMAN]

I agree with Ken.

John,

My 81 Coupe does the same thing. It was worse the other day before I had the 795 CFM Edelbrock carb tuned.
I am thinking of doing a compression test, both wet and dry, to see if the seals are cactus. I suspect they are as there is a little oil being used between changes.
Either way, the compression test will show where the problem lies.
I might add that we had the heads off a little while ago and the head gaskets were genuine GM, used in production. I suspect and my mechanic agrees, that they have never been off in 22 years. We found a little carbon, from the seals letting oil through, I think.

Cheers

Tony

 

[Grasshopper]

If its black smoke it IS fuel. Is your 81 carb or f/i. If its carb, what type. something is allowing fuel into or overflow holler back.

 

[johnd]

it is carb and it is the original as far as I can tell. how would I fix it??

 

[Grasshopper]

Hey johnd,if its aquadrajunk take it off and put on a HOLLEY when the needles and seats stop sealing the flow of fuel it will over flow into the engine. I would goahead and rebuild the carb.with of course agood acid dunking.But i gotta tell you i have never been happier as when i put that HOLLEY 600 on mine w/the adapter plate. runs so much better and way easier to adjust and tune!

 

[johnd]

what I am trying to do is leg it out till the end of next summer because I am ordering the 395hp zz4 from sallee chev and I don't want to drop much money into the motor till then, and the technacality that I do auto body not auto mechanics really isn't a good thing.