Urethan Foam sealant for Cars?

[gdizzle]

Is there a foam sealant for cars? Designed to take heat? I NEED TO SEAL UP AROUND THE HEQTER CORE box. Ideally wont expand too much. Had to enlarge the holes on the box in order to get the Heater core pipes to go through. Now large spaces.

Also is there a silicone sealant that I can use in the engine side to seal the in/out area where the tubes come in? The old sealer/gasket fell apart. Same thing around the heater motor.

Also on the outside Air inlet box, would like to seal it as well as it goes up to the body. But dont want something that will cause it to be glued? Like maybe is there a way to make a homemade gasket?
66 ddart L6

 

[nm9stheham]

Urethane foam like Great Stuff is flammable.

However, there are flame retardant foams used for fire-stopping in buildings. Not inexpensive, though. They will flow in the presence of enough heat (which firestops are designed to do...callled 'intumescent') so may not be appropriate.

Automotive seam sealer may be useful for some of the sealing aorund the boxes. How about some flat rubber with oles around the tubes?