Rewiring Glow Plugs

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Dec 6, 2006 | 11:21 AM

bc56845

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From: Candler, NC

Rewiring Glow Plugs

Have any of you completely removed the glow plug controller and wiring and rewired it yourself ? If so what part# relay did you use and wire guage/connector type?

Dec 6, 2006 | 06:26 PM

bigredtruckmi

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From: Huntington Indiana

We need more info as to what year,model, engine, etc.

Dec 6, 2006 | 06:30 PM

Dave Sponaugle

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From: Nutter Fort, WV

I am running a 93 7.3 engine harness with 7.3 glow plugs in an 86 truck with an 85 6.9 turbo motor.

Does that count?

I used the 86 relay wired for manual control in it's stock location.
Bolted the power supply wire to the glow plug wire where the 7.3 controller and relay sit.
And plugged in the 7.3 glow plugs.

Also spliced the wires for the oil pressure, water temperature, ignition, water in fuel, engine overheat light between the 86 truck harness and the 93 engine harness.

What truck year are you working with?
What engine year are you working with?
What type of glow plugs do you want to use?
What type of controller do you want to use?

Dec 7, 2006 | 07:10 AM

bc56845

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From: Candler, NC

It's a '93 7.3 Its got new motorcraft/beru plugs in it, and the stock relay on the controller is wired for manual control. Several of the stock wires have melted insulation near the connection on each plug, and I'm losing about 1v between the relay and each plug. I'm getting about 10.5v at the relay and about 9.5 at each plug

Dec 7, 2006 | 09:12 PM

Dave Sponaugle

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From: Nutter Fort, WV

Being a master electrician I can tell you that the stock wires are not big enough to carry the amperage the glow plugs draw.
But that fact limits the amount of current the glow plugs recieve because of the voltage drop.
The voltage drop will help keep the glow plugs from burning out.

There was a fellow posting a while back that he rewired his glow plugs with AWG 6 wire which is able to carry 4 times the current a AWG 10 wire will. He was burning up glow plugs after the rewire.

I bought an engine harness when I changed my glow plugs to the new style on my 6.9 so I could replace every wire on the engine as well as every connector on the engine.
Since I like manual glow plugs, I used the stock relay that was on my 86.

How would you like yours to work?
Automatic or manual?

I also saw a link recently that I did not bookmark where you could buy a glow plug harness only for about 1/3 of what I gave Ford for the entire engine harness.
I can not remember who posted the link either.