Firewall grommets

[mikester]

To be honest I didnt use sealer on any of the firewall grommets when I put my cars back together. Just new foam rubber AC or heater box gaskets and 3M strip caulk for putting them together. The grommets fit pretty tight and I figured Im never taking the cars out in any kind of bad weather.
If youre really concerned I would use some black Ultra Seal on the grommets before you put them in. Wipe off the excess and I would think you would be good to go.

 

[Ugly1]

At GM Framingham they called it Monkey sh*t... hope this helps

Had a training meeting lead by a guy that worked at GM in the 80’s. Then went to Toyota. Unfortunately never got to ask about his time with GM.

 

[abbey castro]

I think they use the urethane window sealer for around the heater box , grommets, and some of the seams. You can buy it at NAPA off the shelf. If you’re only doing one or two grommets go with what 78Delta88 said.

That is what I think they used. When I did mine, the black stuff was pliable, and sticky and it came off very easily. I used the window 3M stuff as you can shape it to any grommet.

 

[69hurstolds]

If you want a neat and tidy look, don't use the shoot and spray method. You can still seal the grommets with the rtv stuff around the openings either way. Then if you want, you can use the messy stuff.

Depends on what look you were after. If asthetics is important, don't just j_zz that spray stuff all over the place and just use the neat method without the spray-on stuff. If you want to replicate the horrid GM spray job to look more like original, you know what needs to be done.