Manual Glow Plug Install

Locate the glow plug controller under the dash, its a black box with about 10wires going into it (located near the steering column)
the light blue wire is a ground, its completes the circuit on the relay that energizes it and makes the connection between the top and bottom terminals (thus turning on the GPs').

you can either leave the blue wire intact and just take it off the terminal on the glow plug relay (so you could go back to the stock setup in the future) or cut it under the dash and wire it to your switch.

if you leave the wire intact just run a new wire from the small terminal on the front of the relay to your switch. on the other terminal of your switch, you need to run a wire to a good ground. (in my truck i grounded it to the dash, but be sure to scrap off the paint to bare metal if you do.)

Your switch needs to be a momentary ON switch..

By doing it this way your wait light will function as normal if your controller card is mostly working. since the most common point of failure on the cards is the chip that switches the ground to turn the glow plugs on.

Here are some pics of my manual glow plug overide install. I choose to keep the glow plug controller and light blue wire intact, in case I ever want to go back to the factory setup. I ran a new black wire from the glow plug relay, through the firewall, to my switch in the dash.

jfmrj said:

Does a glow plug module card have to be in there for the wait light to come on?

Click to expand...

Yes

where is the glow plug controler card and how do you know if it needs to be replaced

look at M1075's post a bit further up and you will see the pic of the controller. The card is inside the black plastic box. Pull it out and look for burnt marks or leaking capacitors.

Before you condemn your card as being bad, make sure to check the position of the small gauge orange wire on the glow plug relay. That wire is the voltage sensing wire for the card and the TM wiring diagram for its position is WRONG.

The TM states that the orange wire is supposed to be connected to the same terminal as the red wire from the resistor bank on the firewall. If it is hooked up that way, the controller will not energize the relay. The WAIT light will come on and then go out like it is heating the glow plugs, but nothing will happen with the relay.

The correct location for the wire is on the same terminal as the two large orange wires that feed the glow plugs.

Later,
Joe

I'm a little confused. I set up my manual glow plug switch (in an otherwise stock system) with one wire going from the terminal where the blue wire used to be (as pictured above) and the other to a 12V ground on the dash (a screw under the cigarette lighter). I hear the relay click and the GPs seem to be getting warm when I hold my switch, as it starts easily when it's cold. But, is it supposed to be hooked up to 24V somewhere, or is my 12V cig lighter ground OK?

Edit: I am using Wellman 070s, by the way.

Thanks

A ground is a ground, makes no differance what the voltage.

Just to Clarify this, the relay is fed 12v to one small terminal, the other small terminal is the light blue wire, and is connected to ground via a switch (or controller in the stock setup) grounding it activates the relay, which then feeds current through to the glow plugs.

Nice to hear about - Sorry- read about problems which we served in Germany at laest 10 yeas ago.
Glow plug contollers fail latest at 120,000 miles.
The glow plugs are 2.8 Volts with an pre installed registore. Glowing time is a max of 6 secondes, the seat belt fixing busser is close to that. If you glow over 7 seconds, you won the first price: The glow plugs are dead, worst case senario: take out the engine, remove the heads the get the debris out (Can be done easier if you know how to!).
I know what I'm talking about, I only did it twice!. one time n my military Balazer, one time on my M715. I thought I did no mistakes due to all the work on it ... F..it
Wolf

Wolf.Dose said:

Nice to hear about - Sorry- read about problems which we served in Germany at laest 10 yeas ago.
Glow plug contollers fail latest at 120,000 miles.
The glow plugs are 2.8 Volts with an pre installed registore. Glowing time is a max of 6 secondes, the seat belt fixing busser is close to that. If you glow over 7 seconds, you won the first price: The glow plugs are dead, worst case senario: take out the engine, remove the heads the get the debris out (Can be done easier if you know how to!).
I know what I'm talking about, I only did it twice!. one time n my military Balazer, one time on my M715. I thought I did no mistakes due to all the work on it ... F..it
Wolf

Click to expand...

For the Wellmen plugs They dont swell, they are self-regulating. When they do burn out, you just pull them out and put new ones in (always replace as a set of course)

Why does your m715 have glow plugs?

I once had a Hanomg engine for more than 20 years in my M715. I quit it for the injection pump housing was not seviceable any more and the other spare parts for the engine were not available any more. So I installed at second restauration a 6.2 litre Detroit Diesel engine, which I bought factory fresh in 1996. It is a 1984 engine according to the labels. I modified , due to it was a "Blazer" engine, the flywheel, the clutch, the bellhousing, a new adapter (home made) and some "minor" things. So I came to use the Blazer electric system with the glow plugs and most of the other stuff as well. I siuts me fine, it is according to my needs. And if the quality of the generators, the injection pump and the starter would be better, I would have no reason to claim.
I know what I'm talking about. My M715 is at about 103,500 miles, I got it at 18,124 miles. I think almost nobody drove as many miles with a M715 as I did.
By the way, if CATTLETT 1984 would have checked my engine bay photo propperly, he would have noticed:It is not a straight six engine...........
Wolf
Dipl.-Ing. Maschinenbau
amtlich anerkannter Sachverständiger für den Kfz-Verkehr

I don't think he looked at the photo close enough to notice that it was a M715 instead of a CUCV... LOL

That's certainly an interesting vehicle... I'm impressed that you made the 24V system work in it.

Later,
Joe

Wolf.Dose said:

By the way, if CATTLETT 1984 would have checked my engine bay photo propperly, he would have noticed:It is not a straight six engine...........
Wolf
Dipl.-Ing. Maschinenbau
amtlich anerkannter Sachverständiger für den Kfz-Verkehr

Click to expand...

There is no reason to get your panties in a bunch.
Usually when you start talking about a vehicle, it is assumed it is in the stock configuration, unless you explain what you did to it.

Take it down a notch or two

Crash_AF said:

I don't think he looked at the photo close enough to notice that it was a M715 instead of a CUCV... LOL

That's certainly an interesting vehicle... I'm impressed that you made the 24V system work in it.

Later,
Joe

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The glow plugs are NOT 24v, only the starter is. So swapping the engine in, is painless (as far as the electrical goes).

Sorry if I hurt anybody's feelings or pride or doubted in anybody's qualification on military vehicles.
But if I read about probelms, which are realy old and at least in Germany a long time ago served, I silightly start do doubt a little bit on this and that......
Anyway, the tip on Wellmen glow plugs (of which I never heard befor). On which Voltage do they run: 2.8, 12 or 24 Volts. Do they have the same connectors as the 2.8 Volt glow plugs? Or are they HUMMER plugs?
Sorry for inconvenience
Wolf

I meant the dual alternator 24V charging system... I knew the glow plugs weren't 24v...

Later,
Joe

The alternators are 12 Volt 100 Amps standard stuff (57 Amps will also do it, if you do not serve a military radio).
The system is relatively simple: the left generator serves the front batterie, the right generator the rear batterie. Together 24 Volts. For harness details check TM 9-2320-289-20.
Do not forget the little diode!
Wolf

Wolf.Dose said:

Sorry if I hurt anybody's feelings or pride or doubted in anybody's qualification on military vehicles.
But if I read about probelms, which are realy old and at least in Germany a long time ago served, I silightly start do doubt a little bit on this and that......
Anyway, the tip on Wellmen glow plugs (of which I never heard befor). On which Voltage do they run: 2.8, 12 or 24 Volts. Do they have the same connectors as the 2.8 Volt glow plugs? Or are they HUMMER plugs?
Sorry for inconvenience
Wolf

Click to expand...

they use the standard spade connector (slightly larger than the connectors on the cucv wiring harness.) and can be purchased with a set of the waterproof connectors from

http://www.indusadist.com/web_site_new_2008_005.htm

That means the 2.8 mm wide spade connectors, I asume. Well, than I think, that are the HUMMER glow plugs. We made addapters for that allready.