CUCV M1009 electrical issues

[MMSINDUSTRIES]

I have recently bought a Cucv m1009 that was slightly disassembled. I’m having no good luck finding solid for sure answers for my questions. I would like to start this thread to help others like me.
So to start off.
1. Battery terminal connection I cannot find a clear picture of how the battery’s should be correctly hooked up. See attached image.
2. I would like to know a list of the tail light/turn signal lights, aswell as all of the small marker bulbs
3. My Cucv is missing the gen light harness they were completely cutout and I cannot find any cut wires except for one black wire. I was having an issue with the engine not spinning over when I turn the key so I grounded that wire after checking numerous other things. That did the trick, the truck starts with the key and charges now but I want to make sure this is right. If someone either has a diagram of the gen light harness or a clear picture of the wiring so I can know where to start.
I would like to keep this as a on going thread that other people can update aswell as I can. I’ll add some other pictures of my rig. I’ve done quite a bit of work in the dews weeks I have had it. Thank you

 

[Barrman]

Since the belt is missing from the passenger side alternator and the front battery negative cable seems to be going to the firewall Buss bar. I have to ask if your truck has been converted to 12 volts? If so, search for the Roscommon conversion to see how things are supposed to be wired.

If it is supposed to be 12 and 24 volt. Then the Technical Manual is your friend. The -20 has an appendix at the back that shows where every single wire goes. 1157 for the front running light/blinker. Same for the brake/tail light. Just like any K5 Blazer. Unless your truck is now a 24 volt truck. Then you get to have fun figuring it out.

 

[cucvrus]

the front battery negative cable seems to be going to the firewall Buss bar.
I confused. Where would the stock CUCV front battery negative cable be attached? What I see in the picture is a stock 24 Volt CUCV battery cable hook up. It appears the resistors are still being fed 24 volt current. How about a look at the rest of the engine compartment. Good Luck. I have a few harnesses complete and a few for parts. Let me know. This is easy stuff.

 

[MMSINDUSTRIES]

the front battery negative cable seems to be going to the firewall Buss bar.
I confused. Where would the stock CUCV front battery negative cable be attached? What I see in the picture is a stock 24 Volt CUCV battery cable hook up. It appears the resistors are still being fed 24 volt current. How about a look at the rest of the engine compartment. Good Luck. I have a few harnesses complete and a few for parts. Let me know. This is easy stuff.

This is a picture from when I first got the blazer. I since have put most everything back together and I have the truck running, test driving, cooling properly, charging adequately 13 (+\-) on front battery 25 (+\-) on battery closest to firewall, but I’m just wondering if not having those gen lights will cause a problem. The voltmeter does still work and the “batt” portion is reading about middle of the yellow line when idling. Various dash lights do not work at the moment not sure why atleast the lights that illuminate the gauges.
OFF TOPIC- the blazer takes an awful long time to shift into 2nd gear. The fluid is red and is full. I do believe I am pulling a vacuum from the pump but idk if that shifting problem has something to do with that vacuum thing that is on the side of the injection pump. Some insight on what that is would be appreciated

 

[ezgn]

This is a picture from when I first got the blazer. I since have put most everything back together and I have the truck running, test driving, cooling properly, charging adequately 13 (+\-) on front battery 25 (+\-) on battery closest to firewall, but I’m just wondering if not having those gen lights will cause a problem. The voltmeter does still work and the “batt” portion is reading about middle of the yellow line when idling. Various dash lights do not work at the moment not sure why atleast the lights that illuminate the gauges.
OFF TOPIC- the blazer takes an awful long time to shift into 2nd gear. The fluid is red and is full. I do believe I am pulling a vacuum from the pump but idk if that shifting problem has something to do with that vacuum thing that is on the side of the injection pump. Some insight on what that is would be appreciated

CUCV M1009 electrical issues

I have recently bought a Cucv m1009 that was slightly disassembled. I’m having no good luck finding solid for sure answers for my questions. I would like to start this thread to help others like me. So to start off. 1. Battery terminal connection I cannot find a clear picture of how the...

www.steelsoldiers.com

Your batteries are not charging. You need to check the the Gen lights and replace all the lights in the dash that are not working. Make sure you are running a stock 12-24 volt system. Without the Gen lights you will not be charging your batteries if the system is stock. Your volt meter should be well past the green. The VRV valve on the injection pump regulates your shifts. loosen the two nuts on the side and move it forward or backwards to adjust the shift points. Forward towards the firewall moves the shift lower, towards the radiator move it higher.

 

[cucvrus]

The volt meter you speak of. Is it in the cluster? And if so may I see a picture of it? And the vacuum control valve has 2 connections. Top to transmission and the bottom to the back of engine vacuum pump. The rubber block on the VCV does not need to be there. If it is cracked and leaking do a direct connection. Make sure tyhe rubber vacuum lines are connected and solid. Most are collapsed and dry rotted. Go from there. Lets see the voltmeter.

 

[MMSINDUSTRIES]

CUCV M1009 electrical issues

I have recently bought a Cucv m1009 that was slightly disassembled. I’m having no good luck finding solid for sure answers for my questions. I would like to start this thread to help others like me. So to start off. 1. Battery terminal connection I cannot find a clear picture of how the...

www.steelsoldiers.com

Your batteries are not charging. You need to check the the Gen lights and replace all the lights in the dash that are not working. Make sure you are running a stock 12-24 volt system. Without the Gen lights you will not be charging your batteries if the system is stock. Your volt meter should be well past the green. The VRV valve on the injection pump regulates your shifts. loosen the two nuts on the side and move it forward or backwards to adjust the shift points. Forward moves the shift lower.

Here is a weird thing when I was test driving it around the battery gauge was moving more towards the green part on the gauge. I covered my bases with getting the alternators tested at a reputable auto electric shop. It was squealing the belts when I was driving it and the gauge was moving. I have tightened the belts since then but haven’t driven it only sitting idle, But I was revving it and it wasn’t moving the gauge or making the belts squeal. Does anyone know how many wires would go to the gen lights or what the harness looks like. I’m working with nothing I can’t even see any cut wires.

 

[cucvrus]

Without the Gen lights you will not be charging your batteries if the system is stock.
This is not true. If you increase the RPM's it will start charging and excite the regulator. I have 2 plow trucks that I put self exciting voltage regulators in the alternators and I have not had an issue since. My M1009 charges perfect on the stock volt meter with no cluster in place. It does require a slight RPM increase just for a moment and then it stays right on the tic mark of the voltmeter when idling.

 

[ezgn]

https://www.steelsoldiers.com/threads/instrument-cluster-cleanup.52821/

 

[ezgn]

 

[MMSINDUSTRIES]

The volt meter you speak of. Is it in the cluster? And if so may I see a picture of it? And the vacuum control valve has 2 connections. Top to transmission and the bottom to the back of engine vacuum pump. The rubber block on the VCV does not need to be there. If it is cracked and leaking do a direct connection. Make sure tyhe rubber vacuum lines are connected and solid. Most are collapsed and dry rotted. Go from there. Lets see the voltmeter.

I know it’s not a great picture I apologize I am at work right now. But I’ve heard other people have these gauges and it means they went in for warranty work at one point because the military was having issues with charging and this was the dummy light if you want to put it that way.

 

[ezgn]

Without the Gen lights you will not be charging your batteries if the system is stock.
This is not true. If you increase the RPM's it will start charging and excite the regulator. I have 2 plow trucks that I put self exciting voltage regulators in the alternators and I have not had an issue since. My M1009 charges perfect on the stock volt meter with no cluster in place. It does require a slight RPM increase just for a moment and then it stays right on the tic mark of the voltmeter when idling.

I did not know that. Thank you for the information.

 

[cucvrus]

(1) M1009 Little Red Riding Hood. | SteelSoldiers
A picture does tell the story. Even with no instrument cluster attached the voltmeter shows a correct charge rate. But either way if you want the Gen 1 and Gen 2 light to work you will need to discover the issue.

 

[MMSINDUSTRIES]

(1) M1009 Little Red Riding Hood. | SteelSoldiers
A picture does tell the story. Even with no instrument cluster attached the voltmeter shows a correct charge rate. But either way if you want the Gen 1 and Gen 2 light to work you will need to discover the issue.

The issue is my gen light sockets and harness are completely missing and I don’t even know where the wires are

 

[MMSINDUSTRIES]

The issue is my gen light sockets and harness are completely missing and I don’t even know where the wires are

I’m

Without the Gen lights you will not be charging your batteries if the system is stock.
This is not true. If you increase the RPM's it will start charging and excite the regulator. I have 2 plow trucks that I put self exciting voltage regulators in the alternators and I have not had an issue since. My M1009 charges perfect on the stock volt meter with no cluster in place. It does require a slight RPM increase just for a moment and then it stays right on the tic mark of the voltmeter when idling.

so what you are saying is that the gen lights don’t matter and if I’m idling it and the voltmeter is in the yellow area that is good?

 

[MMSINDUSTRIES]

Should the voltmeter be in the green all the time when running or just when driving?

 

[GunnyM1009]

Should the voltmeter be in the green all the time when running or just when driving?

In my experience the needle should be in the green at all times. If it gets to the yellow you either have week or no charging. Question though your Gen lights are part of your instrument cluster harness. Has the cluster harness been removed?

 

[MMSINDUSTRIES]

In my experience the needle should be in the green at all times. If it gets to the yellow you either have week or no charging. Question though your Gen lights are part of your instrument cluster harness. Has the cluster harness been removed?

Cluster harness is still intact fuel gauge works Speedo works, glow plug light, fuel in water light, low coolant light, the 2 blue lights in the speedo work

 

[GunnyM1009]

Cluster harness is still intact fuel gauge works Speedo works, glow plug light, fuel in water light, low coolant light, the 2 blue lights in the speedo work

OK and looking back at your photos it looks like from what I can see of one Alternator that the wires all look to be in there. You could just have blown bulbs, fuse, or a bad pcb on the back of the cluster. Also see if any of your fusible links are bulged out or broken. Any of these things can cause issues with the charging system. Speedo is mechanically driven BTW.

 

[GunnyM1009]

Cucv fuse box layout.

CUCV Fuse Box Layout

There are some errors in the TM diagram for the CUCV fusebox. I will attempt to point them out as I find them Here is a "clean" fuse box with all the proper fuses and labels ITEM 2 - Hazard Flasher 3 - not used except for the M1010. The M1010 uses it for Ambulance Accessories 4 - no...

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