gasket or not on water jacket for 35 buick

[Buick35]

I'm still having trouble my water jacket to stop leaking coolant.I've tried various sealant with a new gasket.I pulled it off again and took off the old gasket and am wondering if I should just use rtv,if so what's the best?Thanks.

[Mark Shaw]

How about a photo of the sealing surface?

 

[Terry Harper]

Not sure if you have tried it yet but a plain old gasket with Indian Head shellac compound. 

 

[ABear]

X2 on Indian Head Shellac!

 

Coat both sides of gasket with IH shellac to water proof the gasket and assemble.

 

Be aware though, getting the head back off isn't going to be easy if you use it!

 

Are you sure you do not have a crack somewhere within the head or even block?

 

Just a tiny crack or pin hole in the water jacket around the cylinders or the head is all it takes for water seepage to happen.

[Buick35]

Thanks for all the replies.Greg

[Buick35]

I used the blue RTV from a gasket and so far no leaks.

[ABear]

Report back in a few months the results.

 

Blue RTV is nothing more than a self vulcanizing siliconized rubber that sets at room temperature.

 

I never had much luck with RTV under pressure, heck even no pressure areas like intake manifold or valve covers would still leak..

 

Indian Head shellac, however is a old school tried and true method to seal pressurized things on a more near permanent level..

 

As an aside.. Did you read what Permatex says about Blue RTV?

 

You can go to Permatex website HERE and select TECH DOCS and then select TDS to get the actual Technical document from Permatex..

 

In that document they specifically state what I have outlined in red and snipped in the photo below..

Edited May 13 by ABear (see edit history)