Blower box sealer

[JD1964]

We’re moving kind of slow on the LT1 swap but still moving nonetheless. The front clip is off and currently no engine or trans in car. We cut away part of the AC blower box since the car will be AC delete but still retain heat. We made an aluminum panel to cover the hole and attached with internal brackets and screws so it can be removable for heater core change when needed.

To seal the small gaps around the edge of the panel we’re considering using duct sealer like HVAC or electricians use. It has a flashpoint of 310 degrees. Is that flashpoint safe for under hood use in this manner? It will probably be at least 8” away from any header piping.

IDEAL 1 lb. Block Duct Seal Compound (Standard Pack 6 Blocks) 31-601 - The Home Depot

Protect terminal boxes and flashings from moisture and air intrusion by using this durable Block Duct Seal Compound from Ideal.

www.homedepot.com

 

[Doug Chahoy]

You could always use 3-M strip caulk.

 

[Tuffregal83]

3M strip caulk might work
Used it to seal up my heater box

 

[liquidh8]

I've also used 3M strip caulk

 

[JD1964]

I might take a look at the 3M strip caulk too. The idea is to have something that is easily removable and can also withstand the under hood heat with minimal risk of igniting.

 

[jlat]

hello people: Butyl tape is what they used...
IBBY

 

[Olds G's]

3M Strip caulk for sure

 

[57 Handyman]

I used Glass Setting Butyl Tape from NAPA.

 

[smartin3]

I also used the butyl strip tape from Napa.

 

[Doug Chahoy]

That won’t come apart easily if you ever need to