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System not charging

1984 F-150, 351 M Altinator will not charge battery. Altinator removed and checked three times and checked OK, alt is the rebuild from NAPA, new battery, new solinoid, but will not charge can anyone help? Thank You

What test are you using to come to the conclusion the charging is not happening?

I do believe that charging system has a seperate voltage regulator. Have you tested it? Have you checked your fusible links for an open?

fluke amp meter tester
removed altinator had tested at autozone

regulator is on the altinator and was removed and tested at autozone

Check to see if the battery warning light turns on when you turn the key from OFF to RUN. If the light doesn’t work then the alternator won’t get any voltage to start the exciter field. The bulb could be bad or there is a connection problem in that circuit if the light doesn’t work. If the light works then check the output of the alternator with a voltmeter and see if you have more than battery voltage there. If you do then check the fuse or possibly a fusible link between the the alternator and the battery for a problem.

has an amp gauge no battery light that I can see. Key on gauge shows source voltage

You need to examine the dashboard closely for a battery indicator lamp. If the bulb is burnt out the fields will not be energized and the alternator will never charge.

If the bulb is burnt out then replace that, turn the key on (engine not running), and touch the alternator pulley with a screwdriver. There should be a magnetic attraction and if there is the alternator should produce.

People make alot of mistakes when hooking up an ampmeter. They range from blowing the fuse to not putting the meter inline with the circuit. Can you please post back your battery standing voltage and the voltage with the lights on at lets say 1500-2000 rpm.

Hope you did not blow the fuse in your Fluke as the fuses in my Fluke 87 (somewhat of an industry standard ,but way to much for normal DC circuit troubleshooting) are about 9.00 each.

To add to OK4450’s technique, I find that a feeler gague at the back of the alternator detects this magnetism better (along the centerline of the shaft of the alternator). Sure enough if the alternator is producing you will feel a tug at the feeler gague when held in the correct spot.

The last time I had to replace the fuse in my fluke was 7.00. I have an amp atatchment for my fluke. Finished for tonight will continue tomorrow. Thanks for the info. Will let you know.

Start simple, check all the connections. A bad ground can be a problem.

bulb was missing thanks

Thanks for the update and glad you found the trouble. It’s kind of strange the bulb was missing.

I learned about ‘the warning light’ check years ago after spending hours of troubleshooting time on a Ford pickup that wouldn’t charge the battery. It was one of those lessons you never forget. Anytime I look into a charging problem the light check is first on the check list.