96 monaco windsor no RPM No Charge

[MonacoWind96]

While trying to avoid hurricane Irma,we were packing up to evacuate south florida. and upon running the engine, my "ALT CHARGE" light came on and tachometer fell to zero. Engine still running. noticed battery level not in a "charging condition" and closer to the "H" in "cHarging"

has a Hehr Powerline system on it. checked the connections at the alternator..did not fix. Checked the voltage at the "CHARGE/Maintain" connector on the isolator and it reads ZERO.

now i hear these fancy alternators require power to charge, could it be the voltage regulator? i have a spare alternator i was going to take to a shop and swap the spindle from the old to the new.

but if that hunch doesn't work, got any better ideas? anyone also experience this?

Thank you all in advance!

[oldguy70]

I have the same problem. I am going to pull my alternator this morning.
I have been driving a couple of days to get where I can get parts and was told
yesterday there is a good alternator and starter place 10 minutes from where
I am parked. Will let you know what I find

[twinboat]

Look for a smaller wire to the alternator that has battery voltage on it, all of the time.

It is the battery supply that goes around the isolator to control the voltage regulator. Some are fused and marked Duvac.

[Soppy]

Broken belt ? Some tachometers get their rpm sensing from the alternator.

[oldguy70]

Mine turned out to be regulator. I was recommended to go to a small shop i pulled it out this morning and he had it fixed within an hour of me getting it to him

[MonacoWind96]

on the bottom of my alternator, im reading the 12V field voltage.

but the big lead off the alternator to the isolator.... 0.0

[MonacoWind96]

Originally Posted by twinboat

Look for a smaller wire to the alternator that has battery voltage on it, all of the time.

It is the battery supply that goes around the isolator to control the voltage regulator. Some are fused and marked Duvac.

i have 12V to this.... but nothing coming off the lead to the isolator.

[twinboat]

The main alternator wire to the isolator will not have voltage on it. The diodes block it.

Try jumping the center terminal to the chassis battery terminal or move the wires to one post.

If you get charging after doing that, the alt is good.

The isolation can be tested with a diode tester of a volt meter.

[MonacoWind96]

Originally Posted by twinboat

The main alternator wire to the isolator will not have voltage on it. The diodes block it.

Try jumping the center terminal to the chassis battery terminal or move the wires to one post.

If you get charging after doing that, the alt is good.

The isolation can be tested with a diode tester of a volt meter.

could you explain this a little more... i don't understand lol.

[oldguy70]

Check to see if you have voltage at the 2 posts on the regulator. one post will have voltage all the time and the other will have voltage with the key turned on. If you have voltage with the key on and no voltage coming out of your alternator you need to take
your alternator to a rebuild place as either you alternator is shot or your regulator is shot.

[MonacoWind96]

doesnt charge, but the alt light goes off..... still no tach.

bad alternator?

Originally Posted by twinboat

The main alternator wire to the isolator will not have voltage on it. The diodes block it.

Try jumping the center terminal to the chassis battery terminal or move the wires to one post.

If you get charging after doing that, the alt is good.

The isolation can be tested with a diode tester of a volt meter.

[MonacoWind96]

Bad alternator, was rebuilt. Back to normal