Over charging M37

[lovebloodhounds]

Comeing home today and noticed the gauge showed i was overcharing are it was in the red have not had time to check it out but what might yall think is the problem? Thanks kenneth

 

[amanco]

Over charging? When mine is in the red, there is no charging and you are running off the battery only? Is the red on the right? See the photo of my gauge.

 

[M543A2]

I agree; my M37 is not charging when the gage is in the red also. I had a gage go bad. Replacing it fixed the problem. You need to get a voltmeter on the batteries and see if the volts come up after the truck is started and running at higher RPM than idle. If it does, then suspect the gage. If the volts do not increase, then you have to check out the generator and regulator. This is difficult to do without one of the test sets that allow you to put an insert into the large cable from the gen to the regulator and make checks from the terminals it provides. If you do not have access to a test set, you can take the gen off and take it apart and check out the brushes, armature and wiring. I would suspect the gen; the regulators are tough units, but can fail. The seals can be removed from the screws and the top taken off for checking. If you have never messed with regulators, this might best be done by someone who has.
Regards Marti

 

[lovebloodhounds]

Thank you gentleman i will check it out Kenneth

 

[lovebloodhounds]

I checked the batteries today and i am getting a reading of 30.5 volts is that to much Thanks kenneth

 

[amanco]

If you have the mechanical regulator (not solid state), the TM gives the step by step to adjust it to the proper charging voltage.