Brake booster gasket???

[rsmecham]

Hey guys recently tore out my old brake booster to get a replacement because we think it's leaking and causing some low vacuum pressure as confirmed by our vacuum tests. Anyone know where to find the gasket that goes in between the firewall and if you can just make one yourself with some gasket maker? I know the gaskets are supposed to be sticky foam but I can't find the gasket anywhere. I have a 1986 2.8l V6. Just replaced it with part %54-74040 from autozone.

[Pete M]

this is just a water seal, right? 

[Dzimm]

You can make your own but don't use a liquid that dries or it will be a PIA to get it back off.  The factory gasket is just a piece of white foam that is sandwiched between the booster and firewall.

[schardein]

The last time I changed one, which was a while back, I cut a new gasket from a piece of foam tray liner for a Craftsman tool box.

[AZJeff]

3 hours ago, schardein said:

The last time I changed one, which was a while back, I cut a new gasket from a piece of foam tray liner for a Craftsman tool box.

Pretty much any kind of closed cell foam will work.

[Minuit]

36 minutes ago, AZJeff said:

Pretty much any kind of closed cell foam will work.

[MiNi Beast]

what about cork gasket? 

[rsmecham]

Update: I ended up using some cork-rubber gasket and then used RTV to make sure the seal was good and to fill in the extra space for the awkward sizing and shape. 

[AZJeff]

Cork will work, but it’s not as compliant as the closed cell foam.  The gasket is intended to basically be a water shield against any droplets that run down the engine side of the firewall.