i can't take it. I'm going 12 volt...

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junkyardog
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i can't take it. I'm going 12 volt...

Post by junkyardog »

what do i need to go 12 volt.. do i have to pull the pan and change the oil pump to except the 12 volt distributer.. and a altinator is there a after market bracket for the alternator.. and the starter.. I'm not worried about the wiring because it will all be cut out. is there a diigram on 12 volt wiring for a m37.. I'm not buying one... i can't stand this not charging not starting 24volt 3 phase or what ever the hell it is I'm done with it... i have to trucks neither one runs or charges... 12 volt here i come
junkyardog
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Re: i can't take it. I'm going 12 volt...

Post by junkyardog »

can i use the same distributer but with a 12 volt coil and condenser
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Re: i can't take it. I'm going 12 volt...

Post by j mccormick »

You don't have to pull the pan to change the oil pump, it bolts on the outside passenger side of the engine.

Joe
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Re: i can't take it. I'm going 12 volt...

Post by Elwood »

junkyardog wrote:can i use the same distributer but with a 12 volt coil and condenser
The rural fire department that converted my M37 to 12v did exactly that, with the coil outside of the military waterproof distributor housing.

I'm converting it back to 24v, but the external 12v coil worked fine for the brief time that I drove it before disassembly.
“When a long train of abuses and usurpations, pursuing invariably the same Object evinces a design to reduce them under absolute Despotism, IT IS THEIR RIGHT, IT IS THEIR DUTY, TO THROW OFF SUCH GOVERNMENT...” -Declaration of Independence, 1776
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Re: i can't take it. I'm going 12 volt...

Post by Jess »

A proper 24V system is superior to the 12V anytime. But, the harness after 50yrs likely needs replacing. If you go through the whole electrical system, and fix whatever is wrong, you will not have any further issues. Patching it up will just lead to frustration. I have an M37 that I bought from the army disposal sale in 1977 and its still 24V. It will start every time, even when the batteries have been sitting for months. Try that with a 12V setup. If you do change to 12V, keep in mind that more than the light bulbs will need to be changed. Have fun whatever you do, but keep the 24V stuff so that you can change back when you realize that it was as good or better than 12V.
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Re: i can't take it. I'm going 12 volt...

Post by Elwood »

junkyardog wrote:what do i need to go 12 volt.. do i have to pull the pan and change the oil pump to except the 12 volt distributer..
If you convert to the civilian distributor (non-waterproof), then you'll also have to convert to the civilian oil pump.
...and a altinator is there a after market bracket for the alternator
Not that I've seen. The 12v alternator (from a '73 Pontiac!) that was on my M was cobbled on with the stock adjustable bracket on top, and a hunk of steel welded between the engine block (!) and the frame (so much for the Floating Power flexible engine mounting) for the lower alternator mounting point.
.. and the starter..
The 12v or 6v starter is different, and you'll likely have to change the flywheel or the flywheel ring gear, too. And there's the issue with the 12v versus 24v gauges, and the lighting. A 24v to 12v conversion is not simple.
...I'm not worried about the wiring because it will all be cut out. is there a diigram on 12 volt wiring for a m37.. I'm not buying one... i can't stand this not charging not starting 24volt 3 phase or what ever the hell it is I'm done with it... i have to trucks neither one runs or charges... 12 volt here i come
Sounds like the wiring, and not the 24v system, is where your problem may lie. Converting to 12v might solve the problem, but only in the sense that the work to fix the wiring as part of the 12v conversion will fix whatever is wrong.

Your comment about "3 phase" has me wondering. Do you have the high-output 100amp 24v system or the regular 25amp 24v system on your truck(s)? Neither one is actually "3 phase", but if you have the 100amp system with the 24v alternator and the rectifier out front by the radiator, you might benefit by the simpler conversion to the 25amp generator system.

I have to agree with Jess: a 24v system is at least as good as a 12v (except perhaps for the generator vs. alternator performance). Even the new auto manufacturers will be going to 48v systems in the near future.
“When a long train of abuses and usurpations, pursuing invariably the same Object evinces a design to reduce them under absolute Despotism, IT IS THEIR RIGHT, IT IS THEIR DUTY, TO THROW OFF SUCH GOVERNMENT...” -Declaration of Independence, 1776
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Re: i can't take it. I'm going 12 volt...

Post by junkyardog »

3 phase was just a joke. trying to get some fun out of this... i put a regulator and a generator from a running truck on this truck .. it started out charging now it does not.. then it started to run like crap... its just agravating
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Re: i can't take it. I'm going 12 volt...

Post by Elwood »

Yeah, electrical problems can be really frustrating.

Sounds like a ground problem.
“When a long train of abuses and usurpations, pursuing invariably the same Object evinces a design to reduce them under absolute Despotism, IT IS THEIR RIGHT, IT IS THEIR DUTY, TO THROW OFF SUCH GOVERNMENT...” -Declaration of Independence, 1776
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Re: i can't take it. I'm going 12 volt...

Post by W_A_Watson_II »

Elwood wrote:The 12v or 6v starter is different, and you'll likely have to change the flywheel or the flywheel ring gear, too.
I don't recall a difference when I swapped the M's 230 into my civilian PW and connecting the 6V starter.
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Re: i can't take it. I'm going 12 volt...

Post by Elwood »

I know the flywheel had been changed on my M to allow for the 12v starter.

This might be of interest: http://www.g741.org/PHPBB/viewtopic.php ... eel#p60283

And this: http://www.g741.org/PHPBB/viewtopic.php ... eel#p50399
“When a long train of abuses and usurpations, pursuing invariably the same Object evinces a design to reduce them under absolute Despotism, IT IS THEIR RIGHT, IT IS THEIR DUTY, TO THROW OFF SUCH GOVERNMENT...” -Declaration of Independence, 1776
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Re: i can't take it. I'm going 12 volt...

Post by refit1701 »

My truck was 12 volts with a unknown starter (which is gone now) and I am using the same flywheel. My all new 24volt system with electronic ignition is great. I do get some light flickering at night but I think it's a ground. It charges fine. I use a cut-off switch while not driving it.
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Re: i can't take it. I'm going 12 volt...

Post by LegionPiper »

Hi gang,

I've got to admit, I can purchase Sealed Beam Headlamps pretty cheaply still from Autoparts stores.
12v accessories are also much easier to source, like a Hydraulic Pump that was retro-fitted to my own truck.

I've been looking at 24v to 12v converters.
One that's caught my eye is the SDC 60 Voltage Converter.
http://www.samlexamerica.com/products/P ... spx?pid=72

This will help share the current across both batteries, keeping the charging effort balanced.
( At least that's my hope )

I'm keeping all current 24v accessories in place, this just offers me flexibility to leverage more common 12v devices.

Has anyone tried this idea ?
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Re: i can't take it. I'm going 12 volt...

Post by isaac_alaska »

you'd probably want that converter plus a third battery, even if it's a small battery, to help smooth out any current spikes you might see. I don't know how much peak current your hydraulic pump draws but i wouldn't be surprised if it's more than 60 amps at 12V
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Re: i can't take it. I'm going 12 volt...

Post by LegionPiper »

I started to work on the old girl and discovered that high current Voltage converters are pretty expensive.
Hmmm, back to the drawing board.

Then I started to wonder about 24v Hydraulic motors, and sure enough there are plenty on eBay.
Seem to be ex-forklift ??

It looks very similar in size and appearance to the existing 12v motor.
Going to do more analysis on the existing one to match as closely as I can.

I am hoping that I'll be able to wire directly across the two batteries as in the wiring diagram.

I know there a few guys out there with plows on their Trucks, anyone try this already ?

Thanks
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Re: i can't take it. I'm going 12 volt...

Post by Cal_Gary »

Carter has a plow on his-you might send him a PM....
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