Glow plug relay help needed

[FullMetalSlug]

I have a 1986 m1008 from the Navy and it appears that they have cut out the GP controller card and replaced the original GP relay with an ACDelco 212-367 Glow Plug Controller Kit or something similar. The issue I am having is the relay will only cycle the glow plugs on for about 2 secs and the relay will make a weird noise sometimes before making the usual "thunk" telling me that its powering the GP's.
I was thinking I could swap back to the original style GP relay but I dont know how I would do that with the controller card being gone.

Has anyone dealt with these before and/or know what is the best way to tackle this problem? I have searched on here and through google but everything I find seems to apply to the original style relays.

I found similar replacement relays online for about $90, but I would rather just add a manual push button for the GPs but I don't think the methods that I read on here would work. Any ideas on how to do that with this type of relay?

The first two pictures are of the relay setup and the last one is under the dash where the GP controller card was spliced out.

Thank you in advance for your help. I am still fairly new to CUCVs.

 

[319cssb]

Id check if the glowplugs are working or if they are shot.

 

[90Jimmy]

Why not replace or reinstall the card and use the correct GP relay, those parts are available......problem solved and the you can reference a TM for future trouble shooting. Seems like the easiest path to success....IMHO

 

[cucvrus]

https://www.steelsoldiers.com/showthread.php?149232-CUCV-Snow-Plow-Trucks-and-Spreaders/page20

I just dealt with this same cobble job on an M1009. I changed the glow plug relay under the hood, hooked up everything stock, Pulled and checked the glow plugs, replaced the glow plug card with a new one and BANG. It fired up first time every time. I did have a set back with a glow plug relay that was not isolated ground. Minor set back but in the end. I was victorious. 13G glow plugs and all stock wiring. Customer is happy and paid. Good Luck.

 

[MarcusOReallyus]

Yep. I'm with them. Your easiest way forward is to make it stock. Simplest way to figure out the wiring now, and easiest to maintain in the future. Where you live, the controller card will be the best way to run your GP system.

 

[FullMetalSlug]

Right on guys. Thanks for the input and I will begin research all the parts I need to convert it back. I am just worried about what happened to the other wires that tap into the controller card. There are only 4 wires from whats hooked up now and I think controller card has 7 or so.

Any ideas on how to temporarily wiring up a manual GP switch on this setup? I need to get it to shop so I can do my rear disc brake conversion and seals.

 

[MarcusOReallyus]

Any ideas on how to temporarily wiring up a manual GP switch on this setup?

That's tough without knowing the electrical characteristics of that relay. I see it's got a bunch more wires than the stock setup. If I were there, I could play with it and maybe figure it out, but helping you at a distance is another kettle of badly rotted fish.

How about this: Since you are planning to go back to stock, how about buying the correct relay now, pull the mystery relay, and then we can get you wired up with a manual switch pretty easily. There's already a write up on it in the stickies, and you can work with that and then post back here with any questions.

That route takes us from the unknown to the known, and gets you one step closer to your goal.

Whatcha tink?

 

[FullMetalSlug]

I like the game plan. I have an St-85 GP relay and a momentary switch on order and they should be here this week.

With my wiring all messed up maybe you could double check my plan to get this relay wired up with just a Manuel switch.
1) Top post: 12v power source from positive junction box by the batteries. Currently there is a wire running from the negative terminal of the rear battery to the small bus to the left of the GP relay and then another wire coming from that to the GP relay ( I am guessing that is not right)
2)Small top post: 12v to switch to post
3)Small bottom post: Ground
4)Bottom Post: Orange wire to glow plugs

Hopefully I am on the right track. Would anything be different for a 12v truck?

Thanks again for everyone's help. You guys are awesome.

 

[MarcusOReallyus]

I like the game plan. I have an St-85 GP relay and a momentary switch on order and they should be here this week.

Excellent.

1) Top post: 12v power source from positive junction box by the batteries.

Not the best, but workable. Many are running that way. It will do.

Currently there is a wire running from the negative terminal of the rear battery to the small bus to the left of the GP relay and then another wire coming from that to the GP relay ( I am guessing that is not right)

That's 12v, so you should be good. Not the stock place to tap into 12v but it will do. Double check the voltage with a meter, of course.

Or see my "Muddy resistor bypass" for a better approach. I think AntennaClimber may have a post on a similar approach, if'n I relember kerrectly. He does excellent work.

2)Small top post: 12v to switch to post
3)Small bottom post: Ground

Um, workable, but there is a better way. See below.

4)Bottom Post: Orange wire to glow plugs

Yep. Or more accurately, orange wireS to glow plugs.


So, back to 2 and 3. Yes, that will work, but since you eventually want to go back to full stock, there is a better way. Even if you never do, this is still the preferred way to wire a switch to a relay in many cases.

What you want to do is provide 12v SWITCHED BY THE IGNITION to the top small terminal. Then you want the small bottom going to your switch. The other side of the switch goes to GROUND.


This way your GPs only operate when the key is on. There should be a wire there already that provides this. Check the inputs to your current relay and I'll bet you'll find one that is hot when the key is on.

 

[FullMetalSlug]

Thanks. I knew I was off on something. Although my resistors were removed by the previous owner, I really like how you did the bypass. In the thread it seemed back and forth about whether to use a fuse or breaker, which do you think is better?

So in preparation for this project I was cleaning up the connections on the batteries, positive thermal, and small bus, but I reconnected the batteries the running lights (marker, turn signals, and tail lights) are stuck on. I didn't mess with the lights at all and checked the light switch but they still stay on. I haven't gone through the fuses yet. Have you ever experienced this or have an idea of what I did?

 

[MarcusOReallyus]

Thanks. I knew I was off on something. Although my resistors were removed by the previous owner, I really like how you did the bypass. In the thread it seemed back and forth about whether to use a fuse or breaker, which do you think is better?

/shrug/ Flip of the coin. Fuses are simple and cheap. Breakers can be reset by the side of the road. But spare fuses don't take up much room in a glove box......

So in preparation for this project I was cleaning up the connections on the batteries, positive thermal, and small bus, but I reconnected the batteries the running lights (marker, turn signals, and tail lights) are stuck on. I didn't mess with the lights at all and checked the light switch but they still stay on. I haven't gone through the fuses yet. Have you ever experienced this or have an idea of what I did?

Stuck on sounds like a switch. Could be coincidence. Maybe cleaning things up improved current flow enough to make a borderline switch or relay fail. It happens.

Clean your grounds! When electric stuff gets weird, clean your grounds!

 

[FullMetalSlug]

Update:

Got the GP relay installed with a dedicated 12v wire which is on a 100amp breaker from the battery. I went ahead and replaced all the glowplugs with AC60g's. The originals seemed to be working fine but were pretty gunked up and wet. Came up with a pretty sweet spot for the GP switch and future switches, radio location. I will post a picture when I get everything dialed in. Anyways, everything works great and the truck fires right up after to cycles of the switch in 0 degree weather. Thanks for all the help!!!

I still don't know whats going on with the lights staying on and blinkers not working. I replaced the light switch but that didn't do anything.

 

[MarcusOReallyus]

I still don't know whats going on with the lights staying on and blinkers not working. I replaced the light switch but that didn't do anything.

Hmmmmm......

Clean your grounds! When electric stuff gets weird, clean your grounds!