Smoke under the hood

[Guinn]

Had a little fun Friday. Went for a spin in the 'hood and the B popped and sputtered some every time I would slow down, then step on the gas. Backfired for sure just a block from home, and as I stopped the engine, SMOKE billowed out the side of the hood! Popped the hood and my black foam filter was blazing. (Weber downdraft carb). Of course it was also dripping black sludge all over and into the carb! What a mess. Took the carb into the shop and tried to soak off the crud in gas, no go, lacquer thinner, no go. Alky and paint thinner did nothing. In desperation I sprayed Gunk engine cleaner in there and it worked! Of course I had to use one of the wife's good painting brushes to get down around the jets, but she forgave me. /ubbthreads/images/graemlins/cheers.gif

Put it all back and started the B up yesterday and it ran awful. I started to remove the carb again for more cleaning - or disassembly - and noticed a crack in the spark advance vacuum hose. Just a crack. Got a new piece of hose and Voila! Engine is running very well, thank you! So, checking for vacuum leaks is now at the top of my list whenever an engine suddenly starts running poorly. FWIW, Guinn /ubbthreads/images/graemlins/yesnod.gif

 

[John Moore]

Did the weber have one of those 'foam' filters? If so they are bad news. They get full of grease, harden up, and are prone to fires if the car back fires through the carb.

I hope it wasn't too bad. Get a K&N or a paper filer.

 

[Guinn]

Thanks, John. Yep, it was a black foam filter and you just tripped a relay in the brain. I had washed the filter with gasoline a few weeks ago. That probably left a nice coating of flammable stuff in the foam! I have been looking at K/N type filters but don't know how much clearance there is under the hood, so don't know what filter to get. But it will be done. One fire is all I want!!!