No Resistor Bank on 24V system/GP not working

[208007344]

I have an 86 M1009 which is still a 24v system (or so it seems), it has 2 batteries and a 24V starter that I have rebuilt. However, there is not a resistor bank on the firewall to accomplish the required voltage drop? The problem is that my glowplugs are not getting power, which is when I discovered that there was no reisitor bank - had not looked previous to this as all was well. There is a wire with a fusable link in it that runs from the negative side of the back battery to a two stud terminal strip beside the 12v GP relay on the drivers side firewall. From this terminal strip it runs to one side of the GP relay. I have 12v at the strip and at that side of the relay, but not on the other side of the relay nor to the glow plugs when the wait to start light it on. I was going to replace the relay as I suspect that is the issue, but it does "click" when the cycle is almost complete. Questions - Why would my truck not have the resistor bank, or better yet is there a need for the reisitor bank since I already have 12v coming straight off the back battery to the GP relay? Is it possible that replacing the relay will fix the issue of my GP's not getting power? I seem to remember seeing a NAPA part number for the relay that would work but can not find it again? Help anyone?
Thanks-
Travis
86' M1009 CUCV

 

[doghead]

Someone has removed the resistors and resupplied yourGP relay with 12 volts. That will work just fine( I actually recommend making that modification, to eliminate a cause and effect issue that the trucks have in stock form).


The relay is "triggered/switched" by the light blue wire making ground.

You should have 12 volts on one small terminal, and when the controller card says, Turn on, it grounds the relay with the blue wire.

You can manually override the controller circuit buy using a jumper wire on the blue wire(terminal) and touch the other end of your jumper wire to a clean ground. That should trigger the relay.

If you have voltage on one side of the relay(large terminals, but not the other side, with the relay energized(with a jumper on the blue wire), then your relay is bad.

Just be sure you have 12v on the other small terminal to begin with.


A suitable replacement relay is an ST-85 NAPA

 

[208007344]

Thanks Doghead, so it seems that I either have a bad relay or a bad control card ? Hopefully the relay as it appears to be less expensive fix.

Thanks again-
Travis
86 M1009 CUCV

 

[tbearatkin]

Make sure you check all your GP and make sure they are good. Pretty sure a bad GP resistor is what fried all of mine plus the GP relay.


This is what I did at this link.

http://www.steelsoldiers.com/cucv/56682-what-why-did-smoke.html

I removed and tossed the resistor(see the last picture) and bypassed the 24V busbar with a battery cable to the neg post of the back battery. My wait light also would come on and go out but did nothing since the glow plugs were bad it was hard starting.

1. all glow plugs were no good so I replace them with the AC60A
2. glow plug relay was bad so I replaced it with a CQ 56-2432 (carquest)
3. resistor pack was bad removed it and used a 48" long battery cable to bypass the busbar to 12volts on the the battery.

No major issues since then minor issue windshield washer pumps fluid on the windshield when the wipers are turned on and no horn. Will trace these down

 

[208007344]

It appears that it is a bad relay after performing the test doghead suggested. I am going to replace the relay tonight and hopefully solve the problem. I hope the bad relay has not ruined the GP's as they are fairly new. thanks for the help.

 

[doghead]

BEFORE you install the new relay, test it. Be sure that there is NOT continuity between either of the small terminals, to the mounting tabs.

 

[208007344]

Thanks, the new relay did the trick.

I have a fuel leak that appears to be coming from in the valley towards the back of the engine. Is there a common place they leak ? Really hoping that I do not have to take the manifold off.

Thanks-
Travis

 

[doghead]

If you lucky, it's the fuel return line. If your not lucky, it's coming from your Injector Pump.

 

[Jake59]

Hi,

The link unfortunately the link no longer exists.

Jake

 

[MarcusOReallyus]

Jake, the Technical Manuals (TMs) will walk you through the troubleshooting process. They are free for download from this site.

I spent a week in your fine country a few years ago. Well, okay, more than a few. More like 42 years ago. =:O

Beautiful place. I enjoyed the beer, too!



EDIT TO ADD: Here are the TMs that are specific to the CUCV.

 

[Jake59]

Jake, the Technical Manuals (TMs) will walk you through the troubleshooting process. They are free for download from this site.

I spent a week in your fine country a few years ago. Well, okay, more than a few. More like 42 years ago. =:O

Beautiful place. I enjoyed the beer, too!



EDIT TO ADD: Here are the TMs that are specific to the CUCV.

Hi Marcus,

Thank you for your reply. The TMs are a great help in restoring my M1009. This particular CUCV was in fact "stationed" in Belgium on one of our Air Force airfields and where we had a USAF detachment for decades (not sure if they are still there now)... but for sure it is no longer the same team as back then... .
I think it was used as a "follow me" type vehicle for a while at least, as there is a lot of bright yellow paint underneath the cammo paint.

Thanks for your nice compliments about Belgium. We do have the greatest beer (4000 different kinds of beers actually and a lot more then we can handle )... and chocolate of course... but other then that... well, I am proud to say I am more of an American in thinking, beliefs and heart!!
I will bring some beers along when I get to come join you all on one or another occasion!!

Regards,

Jake