what type of sealent should i use on a small block chevy intake manifold on the front and back intake to block area. over the years i have found that the rubber gasket strips that are supplied with the manifold gaskets never seal quite right and leak after a little while. i asked the local mechanic what he used to fix this problem and he told me that i should use sealent insted of those rubber gaskets well after recently useing ultra copper sealent instaling a torker manifold on my 300 zx it leaks oil right in the middle and it seems to be getting worse i cleaned it very well with solvent and used about a 3/8 bead of sealent being careful not to move or bump the manifold during instlation
and it still leaked. is ultra copper sealent ok to use on this or should i use something else it has been good on everything so far but i have never replaced a gasket with it.
Ultrablue or ultracopper works fine for this application. When you applied the sealant, did you let it skin over for 15-20 minutes before installing the manifold?
Tester
Don’t do-not use those rubber gaskets on the lifter valley. They will always leak. A nice fat bead of RTV, or Ultrablue like Tester said, making sure to get it in where the head meets the block deck (usually forms a little step there) will seal things up correctly. Also, you want to drop the manifold straight down in to place and not slide it around, or you’re going to mess up the seal.