CUCV GEN2 wiring Gremlin on 1986 M1008..assistance needed!

[glimmertwin01]

CPF240 relay was replaced.... Warthog.... yes it sounds like im screwed till it gets warm....
I have learned alot reading your wiring help and I looked over F-1 and thought... hmmm maybe that is the culprit, but nahhhhh couldnt be.... i was tracing circuits on f4 and f9
I just took a picture of my 24v buss... just waiting for it to show up in my email. I will post it and perhaps you can show me which wire is the 24v GEN2 feed wire....
After i replaced the inj pump throttle shaft bushings the thing starts right up with 2 GP cycles in this single digit weather... but im sick of having to recharge the battery after 3 or 4 starts....

 

[Warthog]

i restore the old square bodies.. ive worked on many electrical issues...this dual system has me scratchin my head

The wiring is different than the Civvy version but it is very simple once you learn it.

I have about seven square bodies at this point. 4 3/4t Burbs and 3 M1009 blazers.

 

[glimmertwin01]

as promised.. here is my busses with the covers off... If you could mark or indicate which wire needs to be replaced /repaired it would be grateful its getting colder and dark here...
Oh yeah Ive replaced pins/ tabs in the engine side pass thru before... not fun on a nice day...
question... why when i connected a jumper from the 24v buss to the terminal marked V/MTR, did I still not get a GEN2 light?

 

[glimmertwin01]

oh i could post a ton of pictures of my Iron.... my stable includes
1968 chevy K20 292, 1968 GMC K1500 V6, 1973 K20 suburban, 1973 El camino, 1974 K20 pickup,1974 K5, 1976 K20 grass fire truck, 1986 M1008, 1993 K2500 suburban, 1996 Caprice 9c1 unmarked cop car... I have a few....LOL

 

[Warthog]

The arrow points to the wire that should be the GEN2 link.



I see some additional wires attached to the buss bar.One larger black wire on the positive and two small ones on the negative.Do you know what they are? Also there is a nut missing on the negative bar.

Looking at the condition of the terminals, you may just need to take all the wires off and clean the contacts. Disconnect your batteries first.

Don't know the answer to your question. I'll have to think about it. There may be other issues.

Going home for that day. Have a great/warm weekend

 

[glimmertwin01]

black wire is the jumper to my starter solenoid /relay just out of the picture.. the red wire on neg buss is the ground for the relay. and yes i noticed the nut missing and the 2ga ground strap on it was not attached.... I have better luc when things have not been "tampered with by previous owners who dont know what they are doing....
Thanks Warthog... Ill be posting as i accomplish my "fixes"

 

[63bravo]

in referance to the gen two light , try removing the fuse box assy and check that circuit with the low voltage reading , ck the wires feeding the back of the box , preform a wire wiggle test and watch any voltage changes, i hope this is helpful

 

[glimmertwin01]

oh joy... i thought about that yesterday when it was 5 out... broke or discovered a bad pin that feeds the 24v in the pass thru. hope my ham hands can get the bad pin ( spade) to release out of the connector and i can find one... i have rebuilt several engine harnesses in the past.... much easier out of the truck in nice weather... **** "polar vortex"

 

[Warthog]

You might contact HAWKMAN or HillbillyWizard (in your area) and see if they have an engine harness.

 

[glimmertwin01]

talked to one member who is parting these in the hudson valley to see if he had the cab side harness.. didnt catch the handle... just saw the ad on here.

 

[glimmertwin01]

in this cold I think i will have better luck replacing that pin and putting a new fusible link in and see whats up. the truck runs fine but ill have to resort to opening the hood and charging the back battery,,, PITA. now i wish i had the slave plug so i could "make" a 24v charger so the task would be simpler.... but fixing the issue is the best way.

 

[glimmertwin01]

hmmmmm Warthog, i was reviewing post number 15 and the schematic.... sounds like "IF" this wire is the problem, i should disable my "fix" to the starter for the time being.... I could create a schematic of how it is wired now to clarify, but first things first... get 24 V to that pin and into the truck.

 

[glimmertwin01]

think I found the issue... the wire broke off the back side and cleaned out the cavity if the copper oxide... clipped it back to good copper wire... 25.36v hmmm think that could be the issue?

went to the bone yard and pulled a engine side bulkhead connector off and removed a spade terminal.... .. ill have to solder it in the line and see where im at

 

[glimmertwin01]

repairs made.. crimp connector soldered and shrink tubed...

connected batteries turned truck on... i have about 22v and +/- 22v at volmeter in truck in voltmeter plug, but no GEN2 light.

BUT... I have 22.08 V at brown exciter wire even with NO GEN2 llight...
wierd....

 

[glimmertwin01]

ok here is stupidity,,,, i was thinkin,,, hmmm wonder if i need to plug the alternator in.... YUP..nasa I have GEN2 light now its time to charge the batteries since i have been running the tests Key on.....

 

[Warthog]

Sounds like you found the main issue. The GEN lights will not light unless the exciter wire is hooked up and the alternator signals the circuit to close. There is an instruction manual that explains how the exciter circuit works. I'll see if I can find it.

 

[Warthog]

Great.

Run it like that for awhile and then decide if you want to remove your starter relay setup. It works now so I would leave it alone for now.

Sometimes a problem just needs an extra set of eyes to find it. All your past training/experience has come in handy.

Now a bit of house keeping. I need to ask you to reread the forum rules about using capital letters in you posts. It is one of the forum rules that you at least try. You started out good but slacked off.

 

[glimmertwin01]

ahhaaha OK the interweb police are watching. thanks Warthog. your help was great as I might have eventually gotten to that lead.. but you saved me time. as I said after reading alot of this forum i have yet to see the problem i had...
I do think i need to do the doghead upgrade because the "fix" i made is now not working... i think it was only because the starter relay was not powered. i charged the batteries for a few hours.... and had to cross the terminals on the remote solenoid... 2 glow cycles and she literally fired instantly... a lil throttle and both GEN lights go out. I still have the usual glowing GEN1 light when the heater is on... but ill live with that... the old school voltmeter is reading just a hair short of pegged at 30v id say like 29.8 or 29.9v

OK the caps thing.... I use them when labeling the generator lights 1 or 2 is that OK? since the original Faria voltmeter is toast i have a autometer 12v one and put the faria face in it and will cross the rear terminals with 300ohms to bring it down.... until i get my replacement... I found a nice one,,,, its a VDO 332 902 18-32v range. hard to locate working with summit to get me one.. the VDO unit has a scale and colors similar to the OE one.

 

[dependable]

Glad you are getting it sorted out. Nice old style volt meter.

 

[glimmertwin01]

here is a picture of the one i want to use....