Ideas to seal firewall hole

[pontiacgp]

I am putting the EZ EFI ecm in behind the passenger kick panel and ran all the wire harness through the firewall hole that was used for the stock ecm wiring. I need to seal that opening but do not want to use silicone or anything that will glue the harnesses in place. I want to seal it but I don't want to destroy the harnesses in case they ever need to be removed.....

thanks...

 

[81Regal]

You could use something like these from OER

OER Rubber Panel Plugs - Free Shipping on Orders Over $99 at Summit Racing

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[fleming442]

An electrical supply house should have a big enough plug to fill it, OR have you test fit a speedo cable grommet?

 

[pontiacgp]

a grommet will help but there is mutiple wire harnesses that go through that hole I want to make sure it is watertight. The stock ecm wires I believe were encased in the rubber grommet to make it watertight but I don't want to make it a permanent install

 

[Turbolq4]

I used a 2" plumbing plug. One of the ones that slide in and then tighten.

i didn't have any wires in there though.

 

[pontiacgp]

I used a 2" plumbing plug. One of the ones that slide in and then tighten. View attachment 121436 i didn't have any wires in there though.

That would definitely seal it but the wires are KINDA important.....

 

[81Regal]

So you are looking for some sealer that stays flexible? Like this

3M 62556252096 3M Products Auto Bedding and Glazing Compound | Summit Racing

Free Shipping - 3M Products Auto Bedding and Glazing Compound with qualifying orders of $109. Shop Adhesives and Sealants at Summit Racing.

www.summitracing.com

 

[Turbolq4]

That would definitely seal it but the wires are KINDA important.....

Kinda...

 

[fleming442]

Just cau'k the hole up.

So, you're saying you have "multiple wire harnesses"; pare them down to one. You don't need the loom inside.

Actually, get one of those bulkhead connectors MHM used- much cleaner and watertight.

 

[Wageslave]

When I ran my Megasquirt setup, I actually cut the plug out of the other harness and reused it. It is molded on but a slit in the side of it and it will open right up. Reseal it with a little rtv so water can't get through between the wires and snap it back in. Between that and the 90 degree clamp, unless you aren't running inner fenders, the harness shouldn't be a leak point anymore.