To RTV or not to RTV

[Johnnyb]

I have the upper and lower manifolds completely off of my 95 5.0. This is clearly the first time the lower manifold has ever been off the heads.

The surfaces are in great condition and clearly no sort of gasket cement has ever been used before.

My question is in reinstalling the 93 lower: do I use clean gaskets on clean surfaces and trust that they will seal, or do I group them up with some sort of gasket cement, and if gasket cement, then what is the best recommendation for lower intake to heads?

THX

-JB

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[yakelys69]

Probably nothing is best if both surfaces are clean, if pitted some RTV around water jackets only. RTV is gas soluble so don't use it around intake ports. If something is used around intake ports it should be something like Permatex Aviation Form-A-Gasket that resists gasoline. Plenty of threads on not using cork gaskets on the front and rear, many use black RTV in those areas.

 

[yakelys69]

Also temporarily using four threaded studs or all thread (5/16x16) in the four corners will guid the manifold down properly without moving the gaskets. Most importantly follow the torquing sequence.

 

[Johnnyb]

Also temporarily using four threaded studs or all thread (5/16x16) in the four corners will guid the manifold down properly without moving the gaskets. Most importantly follow the torquing sequence.

Thanks! Such a simple, but sensible tip to prevent gasket slide!