Sealing carb holders to engine?

I actually meant ULTRA Black RTV but I dont know why your comments are so negative. I have never had a problem with this stuff. I have used it on many applications but the key is to make sure the surface is 100% clean with no trace of oils or dirt. The stuff is very heat resistant and lasts forever. I have used it on rear ends of trucks without 1 drop of oil leaking years after.

I've used the Ultra Black RTV with no probs, and clean all metal mating surfaces with M.E.K solvent

KZBillx7 wrote: I've used the Ultra Black RTV with no probs, and clean all metal mating surfaces with M.E.K solvent

I used a ton of Ultra Black for my rebuild with excellent results, but only on gaskets that seal oil. RTV is like silicone rubber in that gasoline dissolves it. Sometimes raw gas does flood down the carbs into the intake and that will dissolve the sealer.