Mystery Smoke Scare

[gophersnake]

Thanks, folks. Today I came up with another guess: how about a little raw gas, or even fumes, getting past the rings into the crankcase, then catching fire -- say from a backfire through the carb, maybe even through the PCV valve?

On other cars I remember seeing wire mesh over the fitting where the crankcase breather hose connects to the air cleaner. That fitting on my truck is just an open tube. If anything like this ever happens again, I think I'll see about soldering some mesh on there for a flame suppressor.

The smoke sort of reminded me of burning oil, but not exactly. It was gray to white, not especially blue. If it was fumes in the crankcase burning, I guess that would have been some mixture of gasoline, oil and maybe a little crankcase crud.

That engine does sometimes backfire through the carb, usually after a cold start when I don't have the choke set exactly right.

Oh, and sometimes when I've just started it (in the morning, cold) and I'm maneuvering out of the parking stall, the engine will hesitate once or twice and there'll be quick puffs of whitish smoke out of the tailpipe. Other than that, though, I don't usually see any exhaust in the mirror.