Wire question

[JoshR]

I am planning on rewiring my glowplug harness, completely abandoning the factory GP wiring after the GPR. I am tired of having GPs fail after a year, cooking the harnesses and VCGs, making the engine run poorly and necessitating a day under the hood and another $100+ in parts.

I intend to feed a single 12v lug off the GPR for 8 individual 10 or 12ga leads, fed thru grommets in the valve covers; I will use .157 femalebullet connectors to attach to the GPs, as they're a nearly perfect fit. There will also be a connector on each lead just outside the VC to enable me to insert an 60A ammeter to check each GP without having to pull the valve covers. My question is: what type of wire will withstand the temps and oil under the valve covers? I have plenty of new THHN 12ga with the two-part insulation, rated as oil-resistant and good to 90*C. It is obviously hotter than that under the VCs. I have used THHN, however, in the vicinity of the engine with no problem.

Can anyone point me in the right direction? Thanks -

Josh

[RD97]

I had similar concerns with my truck, but approached the solution from a different angle. I upgraded the UVC harnesses and gaskets to the super-duty style, which has heavier 14-ga pins for the glowplugs and costs quite a bit less. I then wired each glowplug through an individual 30amp maxi-fuse and 40amp automotive relay. (The combined resistance of 8 of these relays in parallel is more than the stock GPR, so I don't think there will be a problem with overextending the PCM.)

The link in my signature has pictures of most of it.

-RD


ps. I'll try to put up some pics of the finished installation later.

[u2slow]

I would look at equipment wire... one of the SEW types. The insulation is a silicone rubber with 150°C or 200°C rating. It is oil resistant and usually very supple due to the fine stranding. However, I would check with a supplier if its suitable for what is essentially oil immersion.

I like your thinking on rewiring the GPs. I'm watching this thread.