Carburetor ??carbon??

[Darryl]

I have a 1981 cutlass supreme 3.8 v6 all original 94,000 miles. What would cause carbon pelletts to build up in float bowl of carb???

 

[oldsmobile joe]

that looks like the charcoal from your charcoal canister.

 

[pontiacgp]

I don't know how pellets from the charcoal canister cold be drawn into the carb since that is one a vent system. Did you put any carb cleaner in your gas tank?...if you mistakenly put fuel injection cleaner that could chew up the rubber fuel line but to have that accumulate in the bowl would mean you do not have a fuel filter.

 

[WanaBa442]

Sure it's not a "carbonator" on there???

Either crud from the tank or lines, don't see how else it could get in there....
Looks like mouse turds.

 

[69hurstolds]

that looks like the charcoal from your charcoal canister.

Bingo. It appears the upper membrane of the charcoal canister has deteriorated (had this happen to me) and backed up into the fuel vent system Truth be known, there's also some carbon chunks that got into the engine as one of the ports goes to the base of the carburetor. If you follow the line that says "carb" from your charcoal canister, you'll see where all this goes up on the engine. You'll likely notice that the carb fuel bowl vent is attached to this system. If something goes haywire, there may be a chance for carbon chunks to be blown back into the fuel bowl vent line. Thus the chunks in the carb. I'll bet if you take the lines loose from the charcoal canister and blow them out, you'll get more chunkies.

Clean out the lines, change the canister, or bypass it somehow and you'll end the mystery of the black chunks. Been a while since I looked at the flowpaths during TVS operation cold vs. hot, but my money is on that canister upper membrane breach. The membrane holds the charcoal chunkies inside the canister. Without it, they're likely to end up everywhere in that carb vent system.

 

[MrSony]

I was just talkin about this lol.
https://gbodyforum.com/threads/charcoal-canister-inline-filter.67797/
ck80 posted a decent lil howto on how to rebuild these in my thread.