No Charge Diagnosis

[23 Reo 221]

My 1983 C-125 is not charging the battery. There are 12.2 volts at the battery while the motor is running. the tabs at the back of the ignition except for the one for the solonoid have 12.2 volts while running. What is the procedure for diagnosing this problem?

[Achto 26,558]

Unplug your regulator/ rectifier. Check the outside two terminals on the plug with a muti-meter set on AC. With the engine running, you should have around 30 volts AC across these 2 terms. If this checks out, then your charging stator is good. ( If you have a reg/rec with 2 terms in line together and one below, then the 2 in line with each other will have AC. The one below will be the DC output.)

 

Shut the engine off, set your multi-meter to DC. From the center terminal to ground you should see battery voltage when you turn the key to the run position. This checks to see if your key switch is connecting the battery to the regulator. Ensure that the body of your regulator / rectifier is grounded well.

 

If all the above check out. Plug the reg/rec back in and start the engine. If you do not see 13.5vdc or above at the battery, then I would suspect that you have a bad reg/rec.

 

 

Edited October 12, 2021 by Achto

[953 nut 51,684]

A poor electrical connection anyplace in the charging circuit can cause low voltage output.