Did factory use these heaterbox gaskets to seal the box to the firewall?

[HeavyHauler]

For a 1968 C10 did the factory use these type of gaskets to seal the heater box to the firewall or did they use some type of caulking or silicone sealant?

Is there supposed to be caulking or silicone sealant used between the gaskets and the firewall or just the gaskets alone?

[HO455]

The box to the firewall is sealed with a corded sealant. See post 1034 in the link for the cheaper sealant I used when I installed mine. I also posted a link to NAPA's factory sealant.

http://67-72chevytrucks.com/vboard/s...698377&page=42

[HeavyHauler]

Originally Posted by HO455

The box to the firewall is sealed with a corded sealant. See post 1034 in the link for the cheaper sealant I used when I installed mine. I also posted a link to NAPA's factory sealant.

http://67-72chevytrucks.com/vboard/s...698377&page=42

It is a shame that they advertise the foam gaskets as a type of factory replacement if the factory only used sealant with no gaskets when originally installed.

[jumpsoffrock]

Originally Posted by HeavyHauler

It is a shame that they advertise the foam gaskets as a type of factory replacement if the factory only used sealant with no gaskets when originally installed.

In all honesty I think the average person doesn't want the hassle of butyl tape sealant or whatever you call it. It's gross and annoying. I used it because it was proper, not because it was fun and easy.

Most industries like selling things that are pleasant to deal with--it avoids bad reviews and irritated customers.
The butyl based stuff is not rocket science, but it is not nearly as user friendly as foam or neoprene.

They sell what makes people happy and does the job.

[HO455]

I believe the foam is for inside the cab but, I don't know for certain.

[HO455]

I believe the foam is for inside the cab but, I don't know for certain.

The stuff that NAPA sells is supposed to be the GM modern day equivalent sealant. But both heater boxes I used to make one good one had white sealant. I have been satisfied with the window sealant I used. (No problems yet, fingers crossed! )

It is somewhat remiss of the manufacturer to not to include some information on how the factory did it and where the gaskets are meant to be installed.

[HeavyHauler]

So instead of the round foam pieces in the kit above what did the factory use to seal the space around the heater core tubes as they exit the heater box into the engine bay?

[70STOVEBOLT]

Originally Posted by HeavyHauler

So instead of the round foam pieces in the kit above what did the factory use to seal the space around the heater core tubes as they exit the heater box into the engine bay?

Subscribing. My truck never had anything there, not sure if the factory put anything there or not. I will have to check the factory assembly manual...