Page 29-03 Step 6 Firewall Sealant

[gblwy]

Hi,

Coupla quick questions if I may.

Do you apply the firewall sealant to the engine side of the firewall, or the cockpit side?

This step obviously refers to the perimeter of the firewall upper. Does it also apply to the perimeter of the firewall bottom? I assume the sides of the firewall bottom will need to be sealed.

I'm assuming the firewall shelf doesn't need to be sealed. This has previously been sealed with tank sealant at both ends.

Thanks...Keith

 

[BigJohn]

Kieth,

I think you have to determine the intent here. As I understand it, the intent is to prevent any transfer of air from the engine compartment to the cockpit. This would be especially important in the unlikely event of a fire in the engine area.

The sealant should go on the engine side, and fill all the rivet holes and all other openings. To make the sealing of the rivets more neat, I used a punch to make holes in standard Avery labels, and stuck them around the rivets as masks to prevent the spead of the dreaded "stuff". I pulled the masks off with the excess sealant after about 24 hours, when it was still pliable. See: http://www.mykitlog.com/users/display_log.php?user=BigJohn&project=639&category=0&log=93266&row=12.

I also bought a couple of veternarian's syringes at the farm store. They really made the application of the material much less messy. Don't buy any needles, just the syringes.

This is a messy job. The key to surviving this is to be well organized with all your rags and solvent at the ready. I used laquer thinner, it's not as nasty as MEK.

John