How to protect the electrical wiring in the engine bay from heat?

[sifan]

With two Frantz bypass filters installed in the engine bay where the battery used to reside the surrounding electrical wires are getting a lot of heat from them. These wires were designed to be near a battery that generated no heat. Occassionally the smell of plastic burning will intrude into the car which I became so familiar with my previous car '91 Civic.

What is the best way to protect the wiring from burning heat? Will insulating the wiring work? If so, what would be the best insulation material?

Or let more air from outside flow into the engine bay for cooling by installing a scoop on the engine hood or some kind of air duct; but can this be done without introducing rain/water into the engine bay that will harm the electrical/electronic components of the engine? Has anyone done this sort of modification? If this is doable, I will probably as a body shop professional to install it.

The insulation method will provide some protection to the wiring when car is in idle. It is more like a passive protection. Using air flow is an active way to reduce the heat but only when the car is moving. Any other suggestions?

 

[sbc350gearhead]

They make fiberglass wrap for wiring and such.

 

[brianl703]

The wiring insulation (crosslinked polyethylene) that is supposed to be used for underhood applications is good for temperatures up to 125C or 257F. It's also flameproof; I have applied a flame to it for several seconds and once I wiped the soot away, you couldn't tell.

Some automakers (notably, European manufacturers) have built cars with PVC insulated wire under the hood. When exposed to heat above 140F, this wire insulation becomes brittle and eventually cracks leaving bare wire.

I'd suggest removing the hoodliner if you have one--that will help keep temperatures down.

 

[sifan]

Thanks for the info. Where can I order such insulation material? Do they come in the form of tape so I can just wrap it around the wiring?

My car does not come with a factory hoodliner.

I have covered the entire lengths of all the hoses of Frantz filters with electrical split tubing for protection. I do not know the temperature rating of the tubing, and wonder if it will also generate fume under high temperature.

 

[brianl703]

Not that I'm aware of. The main problem is that any sort of insulating wrapping isn't going to prevent the wires encased within from reaching the ambient underhood temperature. At best, they will delay it for a little while.

What I think would work better is to wrap the Frantz tubing in fiberglass insulation.

Yes, the split loom tubing could very well be generating the fumes. You need high temperature split loom and I can almost guarantee you that if what you're using was bought at a store, it isn't high temp. Perhaps you could cover the hoses in fiberglass insulation and then put the split loom tubing over that?

Check here for high temp split loom tubing suitable for temperatures up to 300F:

https://www.delcity.net/tstore/servlet/pagebuilder?frame=catalog_browse&parentid=282&page=1

By the way, I highly recommend Del City--their prices are very good and they sell many items that simply aren't available at retail.

 

[sifan]

Thanks for the insight. I thought the wiring insulation will keep the wriing cool 100% all the time. I will definitely replace the tubing as you suggested.