Just removed the manifold from my Craftsman 18 hp garden tractor. Inside it appeared to be caked with mold? Is it mold or something else. I did not have time to examine it further since I had to leave for work. Yippee. Certainly I will clean whatever it is and be careful not to allow any to fall further inside. Any thoughts?
Thanks

has it been sitting outside for a really super long time??

I've never seen of or heard of anything like that!!!

Never have either.... if its soft it could be mold. If its hard and black, its more then likely carbon..... Mold wouldn't grow in the manifold with the gas and all... it's a possibility if it sat for a long, long, long...... time.

It has been outside under a tarp for about 18 months. The "mold" almost looked like the corrosion one sees on a battery terminal. It's not black. Far closer to being white. If I can get a good digital photo I'll post it but that's asking alot from my camara.

That is kinda weird.... Btw, when leaving them under a tarp, leave the front grill uncovered so the tarp will vent, because condensation builds up from out of the ground.

Got to manifold and used the shop vac. It pulled it all out as if it were was never there. Almost lint-like. Well it's gone.
Killed the idle linkage when putting the carb back on. Should have put in on before securing the manifold back into place. Got lazy and still have to do it over and buy a new link.