Military CUCV M1009 & M1008 24V to 12V

[shlalom]

Is there a way to convert the 24 volts on these Military trucks to use 12 volts on 2 or 3 extra appliances. I just bought one and will be converting it to run on SVO/WVO veggie oil so there will be the need to hook up possibly 2 different pumps and whatever else will be required. I was thinking just run a 12 V inverter between the 24 V junction and the appliances themselves. That way it wouldn't isolating the two batteries and alternators and a bunch of confusing rewiring. Don't know if anyone here has had this kind of issue before.

 

[Rob 85K5]

Why not convert the whole thing to 12 volt the onle large purchase would be a new starter. I will post a link to the conversion in the morning, I have bookmarked on my other comp.

 

[dremu]

Is there a way to convert the 24 volts on these Military trucks to use 12 volts on 2 or 3 extra appliances. I just bought one and will be converting it to run on SVO/WVO veggie oil so there will be the need to hook up possibly 2 different pumps and whatever else will be required. I was thinking just run a 12 V inverter between the 24 V junction and the appliances themselves. That way it wouldn't isolating the two batteries and alternators and a bunch of confusing rewiring. Don't know if anyone here has had this kind of issue before.

The military runs the lighting and such off the first battery, so you can run accessories off that tap without a problem.

Or you can do the conversion -- http://www.roscommonequipmentcenter.com/news_notes/nn10.pdf is the link I believe the other poster mentioned.

Me, if it works as is, I'd leave it be.

-- A

 

[rockspider]

M1009 or M1008/1028

To me the answer is different if you have an M1009 (K5) or M1008/1028 (K30 pickup)
Both them have a mixed 12/24 volts setup, but very different.
M1008 have dual alternator, one to charge each battery.
The batteries are always in series, just the engine uses both for 24v and the rest of the rig uses only the first battery, for 12v. Having dual alternators there will be no unbalance to the charge of each battery as each one will be charged for the needed amount.
With this setup you can add every kind of accessories, 12 or 24 v, without any problem or upgrade.
The M1009 has a crazier setup, with single alternator and a big bulky relais box that takes the batteries in series for 24v at starting, and then set them parallel for 12v for the running.
This setup cannot balance the batteries if you uses only one of them for accessories, and the relais box is known for giving problems in the long run (often they give high voltage spikes when switching that can burn electronics). That's one of the reasons why so many owners of M1009 convert them to full time 12v.

 

[DieselDan]

The M1009 has a crazier setup, with single alternator and a big bulky relais box that takes the batteries in series for 24v at starting, and then set them parallel for 12v for the running.

Ah,,,wha? NNNope.

The CUCV series (M1008, M1009, M1031, M1010, M1028) runs the same 12/24V dual altenator system. The only minor diferences I know of were the 200 amp upgraded altenators (on M1008A1, some M1028s, and I think the M1010).

The reason most CUCV owners switch to straight 12V is because the glowplug system utilizes 24V (lotta amps, needs both batteries) through a ballast resistors, which drop the voltage down to 12V. The problem is when a glowplug "craps out" the remaining glowplugs will recieve a higher voltage. (Then more more plugs crap out, voltage goes higher, all plugs die, truck don't start).

 

[shlalom]

The military runs the lighting and such off the first battery, so you can run accessories off that tap without a problem.

Or you can do the conversion -- http://www.roscommonequipmentcenter.com/news_notes/nn10.pdf is the link I believe the other poster mentioned.

Me, if it works as is, I'd leave it be.

-- A

Thanks guys, really helpful. That's really what I'd like to do if I can. Leaving it how it is seems to be way more attractive than having to go buy a new starter and fool around with rewiring stuff. I've actually seen that article and he had laid out pretty much a roadblock at every possible way of trying to run 12V accessories. For running stuff off that 12v tap like you said, he warns that it could cause an imbalance in the batteries and wear the one out prematurely. This would make it last 2-3 years as opposed to 4-5, but if that's all I'm dealing with I think it'd be cheaper temporarily than going out and buying a new starter and easier too considering the rewiring. I kind of doubt it would tax the one battery too hard for the conversion I'm thinking of doing. It would be basically running an extra fuel pump full time though, and probably another one during fill-up. Don't know, but maybe it wouldn't be too much strain.

 

[shlalom]

Oh I do have an M1009 though. I'm told it was owned by a police department in GA. Only 51,000 mi. So I'm guessing it's got a lot of life left in it considering how meticulously they maintain their stuff.

 

[DieselDan]

He, He, "military miles" are can be alittle different than civvy miles When we used to service the CUCVs we'd swap the batteries to even out the usage (between #1 and #2).

 

[Cucv_M1008]

@cheavyk10