I have a rather strange case of wierd smoke. 1970 chevelle, 454 turbo 400 and 10 bolt 3.73 posi. Stock rebuilt suspension, 255/60/15 tires. When the car is at operating temp and you are cruising, black smoke appears from the right side rear of the car. There seems to be no ryhme or reason to it. Just steady cruising and it will some time pour smoke out, other times it will be a light puff. Brake inspection reveals nothing abnormal, engine is running well, will do this occasionally on decel but usually when cruising and today it did it most often after driving wide open then slowing down. Definately does not appear engine related.
Right side exhaust tip where joined to exhaust tubing has black soot on it. Left side does not. Could the rear wheel be throwing gear oil, brake fluid or something on to the exhaust causing this smoke? I cannot see any leaks anywhere and this has been occuring for about 2 months now. Really embarrassing. Thanks.

Sounds like a rich condition. I would pull the plugs on the affected side and see if they are black or sooty, if so you need to check the carb for flooding. If you look down into the carb while it is running see if fuel is dripping from squirters if so check float level you may have a bad needle and seat or a float which is heavy with fuel.

Just a thought smile.gif

I agree with the above post. The sooty exhaust pipe is a dead give away. Check those plugs.

I think I may have a solution but it will take a week or three to know. I was passing a bus on I-95 today and when I backed off the smoke appeared on cue. I think I remember removing the oil baffle from the valve covers. I guess since the smoke only appears when hot, that the oil is thinning out and when a high vacuum is built up it get sucked down the intake and is burned on the right bank because thats where the crankcase gases go due to whatever phenomenon or routing of the intake ports.

I'm with the 2 posts. pull the plugs..

I would say that might be the case except the smoke is black. normally oil will have a white blue color to it. What was probablly happening is that as you let off the accelerator, the fuel was no longer being burned and produced the puff of smoke. check the plugs please :D