doing that funky charging thing

[corelokt]

Well, wired, again, my alternator warning lights. 12v power to the left on, through the light, and 24v to the right one, through the other light. Both leads are fused. However, the number one alt still needs to be revved high to make it charge. I had both checked at a shop and both are fine, so what gives?

 

[Michael]

If you know you have two good alternators and the belts aren't loose then it has to be in the wiring. I don't understand the rest of what you are trying to say.

 

[motormayhem]

If you know you have two good alternators and the belts aren't loose then it has to be in the wiring. I don't understand the rest of what you are trying to say.

I think he is saying to get the light to go off the motor needs to be revved. Mine is going the same thing (except it is gen 2) and my alts are good.

 

[mangus580]

Core... you should remind everyone in posts like this... that you keep messing with your wiring... and its NOT stock anymore.

Frankly, I am not surprised at the trouble you keep having...

 

[hobie237]

As a data point, my buddy was having a similar problem, but it wasn't the GEN lights coming on, it was the voltmeter showing low at idle. Alternators checked out OK on the test bench, for whatever reason, required disassembly to find the problem, and I don't remember what that was.

I will say that it would seem odd for the GEN1 light to come on without throwing a GEN2 light and/or tossing off the voltmeter, so if the voltages are proper, it's the wiring to the light.

 

[corelokt]

Actually the Gen lights are fine, it's the #1 volt gauge that is off until the engine is revved.
Sorry about the reply delay, been at work.
So far as I know, even tho I put in gauges and extra fuse boxes, the dummy lights are still wired the same. I'd just like to figure this out.

 

[hobie237]

More details about your gauge setup would be useful. Do you have two gauges that show 12v (or thereabouts) each, or one that shows 12v for #1 and the other that shows 24v for #2? In other words, does the second gauge ground to the #1 or to chassis ground?

I ask this because if there are two independent gauges that show 12v each, and one is screwy, it could be an alternator problem. If the second gauge is a 24v gauge, though, then it should also be impacted by the problems with the #1, and if it isn't, it suggests an instrumentation problem with the gauge for the #1.

 

[corelokt]

Two gauges. One is 12 volt and chassis ground. The is 24 volt and grounded to 12 volt. It seems to be isolated to the #1 alternator. The #2 alternator actually always reads a few volts high, but swings up to its reading real promptly.

 

[hobie237]

The #2 may be making up for the difference by showing high, since it's grounding to the #1.

When my buddy had a similar issue, the solution was another rebuild of the alternator. Personally I'd be tempted to toss a regular, non-isolated ground alternator on in the #1 spot. For some reason these alternators are a bit odd, I think their guts date back much farther than the modern 100A GM alternators (or any other amperage, for that matter), and thus they are simply less reliable.

 

[Westech]

opcorn:

 

[RockyM1028]

Newbie here, Just got my M1028 a month ago! My Gen 2 light was coming on as well"only at idle" so I removed both alt's and brought them in for rebuild both tested good? Had em rebuilt anyways! My re-builder did notice that one of the pulleys was larger thus Running slower? He had a matching smaller pully we made the swap and no more Gen #2 light!

 

[GreenBull]

A difference in the regulator set points between the two regulators?

Assuming both generators are isolated ground have you swapped them? DVOM & tach readings? Voltage drop test done between generators and corresponding batteries?