After my previous post I took my alternator to the repair shop. They replaced the attached voltage regulator. I brought the alternator home and reinstalled it. It is still not charging. When the engine is not running the batt voltage is 12.07. When the engine is running the batt voltage is 11.97. The start batteries are about 3' from the alternator. The wiring looks good and the belts are tight. What do you guys think? Take it back to the repair shop? What else can I do? Thanks.
Make sure the voltage regulator has voltage waiting to excite the alternator - on BAT or IGN terminal of regulator.
Check the regulator wiring on your bus - grounds too.
Check the big cable that goes from the alt to the switch or batteries. I have seen them burned clear thru.
Take one side of your jumper cables and hook one end to the big post on the alt and the other end of the same cable to the + side of the battery.
Sammy made an excellent suggestion and was right on. If You are not an electrical person try My point and shoot fix. Check from ground to all terminals on the regulator. One terminal should have 12 volts on it with the key or master switch on and the voltage should not there with the key or switch off. If that one condition does not exist the alternator will not charge. Try that test and post back, it will make it a lot easier to help. John
Quote from: junkman42 on August 31, 2008, 09:52:19 AM
Sammy made an excellent suggestion and was right on. If You are not an electrical person try My point and shoot fix. Check from ground to all terminals on the regulator. One terminal should have 12 volts on it with the key or master switch on and the voltage should not there with the key or switch off. If that one condition does not exist the alternator will not charge. Try that test and post back, it will make it a lot easier to help. John
I would suggest doing this with the engine running. There may be a safety circuit that prevents the alternator from charging until the safety circuit closes.
Richard
Richard, excellent point, I should have thought of that, now You have a clue as to why I am a retired enlisted man! Old age etc. regards John