firesleeve for wire?

prkaye · #1 10-25-2009, 05:41 PM

I re-jigged some of my firewall-forward routing to allow for a shorter run from my heat-muff to my heater box. As a result, my starter cable is forced to sit about 2" from my heat muff. I worry that this might be a bit close. Is there any kind of firesleeve or insulation that can be wrapped around 2AWG wire to protect it?

N941WR · #2 10-25-2009, 07:17 PM

Phil,

Try one of the heat shields that you secure to an exhaust pipe. 2" is a good distance. Don't forget, there is a lot air moving through your engine compartment to cool such things.

carguy614 · #3 10-26-2009, 04:56 AM

Bill is right, and 2 inches is probably OK for Tefzel cable. To add a little piece of mind, you could slip a little fuel line firesleeve over it. Secure it with a couple of tefzel zip ties, and inspect it at first cowl off after the airplane is flying.

Regards,
Chris

prkaye · #4 10-26-2009, 04:59 AM

what about exhaust-wrap, just in that short section where the wire passes close? I know Vetterman recommends against wrapping his exhaust systems, but I'm only talking about wrapping maybe a 6-inch segment.
Then again, i'm probably worrying about nothing.

chaskuss · #5 10-26-2009, 05:18 AM

Quote:

Originally Posted by prkaye

what about exhaust-wrap, used in the racing world? I could apply that to my exhaust pipes to keep the temps down (this was suggested to me by another forum member for the purpose of keeping my cabin-heat air hot).

Phil,
Using exhaust wrap on the exhaust has a down side. It tends to trap moisture against the steel of the exhaust as the system cools down. It acts like a sponge, keeping the steel damp. This will greatly shorten the life of your exhaust system. I suggest you call Larry Vetterman before installing heat wrap on your exhaust system. Using the wrap on the starter cable would be better. The previous suggestion of a heat shield is probably the best idea.
Charlie Kuss

prkaye · #6 10-26-2009, 05:25 AM

yeah, that makes sense about the wrap being bad for the exhaust.
Can't put a heat sheild there, it's right where my heat muff is. But maybe the heat muff itself will act as a bit of a heat-sheild. The wire sits 2" above the heat muff.
Towards the front i have a similar situation with my alternator wire being about that close to my forward exhaust pipes. I could put a heat sheild there.

Dave Cole · #7 10-26-2009, 06:12 AM

Remember that cool air will always be flowing through the heat muff, so the outer surface of the heat muff will always be a lot cooler than the exhast pipes.

prkaye · #8 10-26-2009, 06:18 AM

speaking of which... what about wrapping just the heat-muff, to ensure the cabin-heat air is as hot as possible? It get's cooooool up here in Ottawa.

chaskuss · #9 10-26-2009, 07:16 AM

Quote:

Originally Posted by prkaye

speaking of which... what about wrapping just the heat-muff, to ensure the cabin-heat air is as hot as possible? It get's cooooool up here in Ottawa.

A ceramic coating like Jet Kote would be better. It won't hold moisture against your heat muff. Plus you can coat both sides of the muff.
Charlie

N941WR · #10 10-26-2009, 07:51 AM

Quote:

Originally Posted by prkaye

speaking of which... what about wrapping just the heat-muff, to ensure the cabin-heat air is as hot as possible? It get's cooooool up here in Ottawa.

Phil,

I recommend this. This will not hurt your exhaust and you will have to remove the wrap once a year to inspect the heater muff. So, any deterioration will be caught fairly quickly.