What sealant is used between subframe and firewall?

[Grimbo]

I've had a bit of a look around but can't seem to find it.

As the title suggests I'm trying to find out what sealant is used between the subframe to the body where the subframe bolts up either side of the firewall?

Thanks in advance,
Sam

[bootlegger]

All the cars ive pulled apart have had nothing. It seems to me they bolted the subframe on and then just run some mastic or even bitumen around the outside.

[Devilrod]

When I bolted mine back on we put something on there and I can't remember exactly what it was. It may have been butel mastic definitely wasnt a silicon based product though, we ran a bead over the section where the two surfaces butted up. I'll try and find out.

[parisian62]

I used butyl mastic.

[oldnek]

Butyl Mastic as Stewart said or Windscreen sealer, don't use urethane.

[Grimbo]

Thanks for all the replies guys. I'm ready when the time comes.

Cheers
Sam

[MeFB]

Sikaflex 227 looks like the go because it's specifically for auto bodies:

http://www.sydneytools.com.au/product_d ... %20227.pdf

I'm a bit surprised that it's PU though, I'd have thought neutral cure silicone would have been the way to go. It's probably because you can paint over PU, but not silicone.

[Brian Westlake]

I'd use black Butyl Mastic as this is a sealant only, whereas Sikaflex is a sealant but also a very strong adhesive that would require cutting off if removal was required in the future.
This may be a big job because of access problems once the 2 parts are bolted together. Heating with oxy acetylene will also break down the bond with much flame and acrid smoke.
I think just rely on the bolts with some mastic in between.
Tony Sikaflex 265 Fiddler.