M37 Voltage Regulator Adjustable??

[70deuce]

I have two older voltage regulators both putting out over 30 volts. Some older manuals show taking out the plug on one lower side of the regulator to adjust voltage. They both have the plug but there is no adjusting screw inside lined up with the hole with the plug out. Do these have to be diassembled to adjust the voltage if they can be adjusted??

 

[Crazyguyla]

this thread has a link to TM 9-2320-209-35. The TM has the breakdown, assembly, and adjustment of the voltage regulator.

http://www.steelsoldiers.com/deuce/57468-tm-9-2320-209-35-c6.html#post666235

 

[rosco]

Sometimes its good to take them apart and look inside. I recently had the same problem. but by the time I had finished trying to adjust it......... I gathered several regulators out of my stash, and found they had been subject to moisture & corrosion inside. I finally replaced the one in the M37, from one off an M211 donor truck.

 

[cranetruck]

I assume that you are interested in keeping a vintage electromechanical regulator for your M37 and if so, I don't believe that there is an outside adjustment. The case would have to come off. There should be one stashed away here somewhere, I'll take a look...

 

[70deuce]

Yes I would like to keep to old style regulator and for Crazyguyla thanks for the link to the TM it has one on the best descriptions and breakdowns of the old regulators I've seen. It shows a voltage adjustment screw on the side of one of the relays. For crane truck it is a vertically mounted adjustment screw if you tear into one. I'll check all airgap clearances on mine first. I have two and they are both way off. Then I'll see how much voltage adjustment is available with the adjustment screw. That manual covers alot of the old big trucks. Thanks again.

 

[JGBallew]

I remember seeing a M37 with a carbon pile type regulator. There was a cover that allowed you to adjust the spring pressure on the stack.

Not sure if that is what you have though, or how common that VR was.

 

[70deuce]

Thanks to Crazyguyla for putting me on to Tm 9-2320-209-35 c6 That manual should be checked out by all who have older vehicles. I was able to adjust the voltage regulator in question down to 27.0 volts from 29.8 with the knurled adjustment screw shown in picture 2 and 3. Loosen to reduce voltage. Its on the bottom of the voltage regulator relay which is the one on the far left or closest to the camera depending on which picture you look at. took me two tries to get it set rigth disconnecting the battery each time before adjustment. I have another regulator reading 36.5 volts I will try to adjust also. Easy to do and saved some cash for a replacement.