M1028 Duallie Generator # 2's Exciter wire trouble light is not lighting

[huggy]

My exciter wire 12v ignition for the #2 generator source doesn't have 12 volts source. I had an ignition problem where my 24V ignition was wired with a push button with a straight 24V source off the 24V block and was wired directly into a purple wire of my wire harness coming out of my fuse box in the engine compartment. So, that I had to turn the key to the on position and then press the button to start the vehicle. "It did have a fuseable link" in the 24 V source going to the push button. I disconnected that 24 volt source, fixed the fuseable link that is in conjunction with the ignitions 5 prong relay and the starter, at the 24 volt block that had burned through. Then I did the doghead relay and put in a new solenoid in the ignition system, but when I was doing this Dog Head relay, I realized that the 24 volt source that was suppose to be coming to thge solenoid was not there!!! Going back to the excited wire problem , I see there's 24V source coming to a relay there that is in line with the exciter wire trouble light down in the same area as the 5 prong relay is at. So, I am wondering if the lack of 24 volts to the 5 prong relay is conected to the problem I am having with the exciter wires relay down in the same area? Is this lack of 24V source coming to my doghead relay somehow connected to the lack of 24V to my trouble light and why it's not exciting my alternator to charge. Also, if I were to do the "rosocommon" conversion to a single alternator 12 volt system, would this fix the exciter wire's lack of 24 volt to the trouble light and let my gen # 2 start charging, again? "Warthog" please give me some advice on this... Thanks, huggy

 

[huggy]

The reason I want to do the conversion to 12 volts, is because from my understanding of what and how it works is that it obviously changes it to 12 volts in parallel, so then my 24 volt would be gone, so I am hoping that the lack of 24 volts to the exciter wire's solenoid down by the 5 prong relay for the starter under the dash would not be a problem anymore. Then the light will light when I turn the key on to start the m1028, and the alternator's eciter wire will be excited! Please any help woulkd be great!!! I am very illiterate to compurters and have a hard time with this sight. I see "Warthog's" informationg on wireing problems and how he says to go to the TM's but I can't even figureout how to get there...

 

[Warthog]

I'm going to have to dissect your post to see what is going on.

Switching to 12v will not fix the GEN2 issue. There is a problem with the circuit and it will have to be fixed before it will work.

 

[huggy]

Great.... I don't know what to look for in this truck. Like I said, I don't believe the 24 volts is at the solenoid/relay under the dash that is by the volt meter solenoid/relay and the 5 prong ignition relay. I had checked for 24 volts at the 5 prong relay when I wired up the dog head relay. But, it wasn't there. So, I don't believe the starter solenoid is getting 24 volts there either. I have had 5 of these trucks and always kept um 24 volts. Cuz, I love how they start so fast! But, I am at a loss as to how to trace the 24 volts for this # 2 gen trouble light. As I have read in your posts that it uses to excite the exciter wire to that alternator. Can you tell me where to look or what to look for in the circuit? Thanks Warthog...

 

[huggy]

The alternator was rebuilt by a friend at his starter and alternator repair shop, that is also an Auto Electrical/Repair shop. We know it is ok, because he showed me with a tester Eire with a little light on it, like the trouble light in the dash wired in it that also,has clips on one end and a alternator 2 prong plug. He plugged it in to the 2nd alternator, and then use the clip to hook to the 12v out put. The came on when the truck is off, but goes out when it's running. The alternator charges though so it is being "excited". I guess that is the word to use. Hope that explains something to you Warthog as to what maybe going on. I just had another bad back surgery 3 months ago, so it is killing me to work on this thing, but there is no shops that understand what is going on. Not even my friends family shop, that has been in this work for EVER! His cousin wanted to just solder the trouble light to the circuit board in back of the dash that it I guess makes contact with when you twist it into it's place in the dash board... I thought for sure was not the answer?

 

[Warthog]

I think I can help but you will need to post some pictures. Can you do that?

If the shop can read a wiring diagram they should be able to figure it out.

I kills me that people just start hacking away at the wiring when they don't understand it.

 

[Warthog]

Can you read a wiring diagram?

 

[huggy]

Hi, Warthog... Hey I just took it to a shop that is a guy who is known all over the country! For real he is wicked. Hesse Automotive in Grand Mound Ia. He is a diesel GOD, he builds racing diesels for Salt Flat time trials and has his own in ground Dyno at his shop.... Anyway, the circuit board is bad where the dash light hooks to it. My next question is can I just go get a circuit board out of the junkyard for another K a Series Blazer, since they are, the cucv's I just a 12 volt system converted? They should use the same circuit hoards then? Thanks, he us messing with the truck now. Any help would be greatly appreciated, Warthog!

 

[huggy]

Hi, Warthog... Hey I just took it to a shop that is a guy who is known all over the country! For real he is wicked. Hesse Automotive in Grand Mound Ia. He is a diesel GOD, he builds racing diesels for Salt Flat time trials and has his own in ground Dyno at his shop.... Anyway, the circuit board is bad where the dash light hooks to it. My next question is can I just go get a circuit board out of the junkyard for another K a Series Blazer, since they are, the cucv's I just a 12 volt system converted? They should use the same circuit hoards then? Thanks, the mech. Is working with the truck now. Any help would be greatly appreciated, Warthog! I did just did locate another good K Series circuit board out of a junkyard truck if it will work to swap them? Thanks for the help.....

 

[Warthog]

A circuit board from a mid 80s truck with idiot lights will work. If it has guages it will not work.

LMCTruck.com has new ones.

http://www.lmctruck.com/icatalog/cc/full.aspx?Page=122

Item 38-8036

I repaired a circuit board a few years ago. Here are some articles that may help

http://www.steelsoldiers.com/showthread.php?43351-CUCV-Instrument-Cluster-Repair

http://www.steelsoldiers.com/showthr...luster-Decoded

http://www.steelsoldiers.com/showthr...luster-Cleanup

 

[huggy]

So, the one with idiot lights will work from a K series truck or blazer then? But, they didn't gave 2 alternators, the mech, says so, how would it work with the cucv having 2 alternators, or foes the cucv wiring just redirect voltage through how it is wired to the 2nd alternators spot? Thanks again..... Like I said I have one located at a junk yard!!!

 

[Warthog]

The circuit board could care less what is sending current thru it. It is the truck wiring that is wired for the GEN1 and GEN2.

As long as the board is laid out the same it will work.

 

[huggy]

Thank you Mr. Warthog! But, just 1 more question, please.... Is the cluster just changed through the relays and diodes to work with the 2nd alt. because the other K Series trucks don't have 2 alts? Thanks, huggy

 

[Warthog]

The cluster is not the issue. It is how the trucks wiring send the power to the cluster. And yes it is done with the wiring, relays and diodes.

As long as the circuit film (really not a board) is the same, it will work with the trucks wiring.

 

[huggy]

Up date on my dually..... It is up and running like the Monster it is!it was missing the relays under the dash, and the diesel tech. Fixed the circuit board problem! Now I got to fix the stupid K Series truck bucket seat that I bought out of a 1ton chevy K Series truck. I put um in the truck and welded the bracket onto the floor so they would work in the M1028. But, on the way to the shop the driver seats back broke and it is now slanted to the right side. NOT GOOD for a guy who just had his spine plated in. The front of my spine. Will the Chevy Suburban bucket seats install without a lot of messing around, or I have some Chevy Blazer seats "in mint condition" from a K series late 70's or early 80's Blazer? Anyone with advice would be great! They look like they will be a pain to bolt to the K series truck buckets rails.

 

[huggy]

Well just got done taking tracks off a set of nice Suburban seats, that are supposed to be able to bolt up to the m1028? I bolted them to a nice set of early 80's Blazer bucket seats. Gonna see if they bolt in easily or not tomorrow. I am gonna have to drill one hole and tap the hole, or just tack weld the one spot that don't natch the bolt hole pattern? Either way it is like Christmas to me cuz I love to drive the truck but it's bench seat was killing my back!!! I just hope they mount up to the spacer bracket that is in the front of the seats corners by the 4 wheel shifter.

 

[huggy]

I am trying to see what kinda of RPM this M1028 dually shoild be running with the 410 gear set KI put in it with the stock 235 tires on it, or 31" tall tires on the highway at say 65 or 70 mph! Warthog, would ya have a clue about, as to what rpm it is running at 65 or 70mph ?or anyone else on this sight? I am not finding anything about this on the computer... everyone just talks about changing tire sizes, but I would like to know what I am running with 410's and stock tires. Thanks

 

[doghead]

One of our site's rules is to NOT post the same thing in multiple threads.

It wastes peoples time and is rude.