What is spitting out of my exhaust?

[phishtaco]

I have something spitting out of my exhaust when I start my 40 up. It looks like I sprayed black spay paint on my wall. This is the first time I've noticed this. I had not started it in about 2 weeks prior to this. Any thoughts? 73 F engine

 

[toddslater]

Probably just a little condensation water and exhaust soot. Does it clean itself up after it warms up a bit ?

 

[phishtaco]

hmm not sure, but I have never noticed it before when I pull back into the garage.

 

[fsusteve]

Carbon/condensation, mine does it, carb needs tuning.

 

[Gumby]

Condensation is normal. If you don't drive it much or let it run with the choke on, it will spew black. All that water is why cars that don't get driven much rust out the exhausts so fast. For some reason the japanese put drain holes in the bottom of the mufflers and American cars don't.

 

[phishtaco]

Good deal, just wanted to make sure it wasn't something out of the ordinary. I'm sure the carb needs tuning

 

[IDave]

It will definitely be worse if you are tuned rich.

 

[ALEXGAR]

I have something spitting out of my exhaust when I start my 40 up. It looks like I sprayed black spay paint on my wall. This is the first time I've noticed this. I had not started it in about 2 weeks prior to this. Any thoughts? 73 F engine

My '71 does the same thing. Folks tell me it's condensation in the exhaust. It usaully paints my white wall black but it subsides after 5 minutes or so.

 

[IDave]

I definitely have less of this since I leaned out my system, but I have the same black "paint" on the walls and floor of my garage and barn. Moisture in your gas will break carbon off of your cylinder walls and accelerate this as well. My Weber-carbed F135 produced a HUGE amount of the stuff when I switched over to the 1 Barrel Aisen. Since then, still some water but not so much carbon.

 

[chuglife]

me too. my truck runs rich, so it all makes sense