60 amp Generator/ Charging Question

[M998AVAN]

1991 HMMWV, 6.2 L, 60 amp generator. Purchased HMMWV noticed bad rattle noise from generator, after inspection mounting ear was broken (someone forgot the spacer). Charging was still good, stayed in the middle green. I purchased a new one from KASCAR and installed with spacer, charging again stayin the middle green. Got In the other day, the more I drove the gauge would slowly drop to mid yellow. I could stop for a few minutes, start it back up and charging would be good, then slowly drop again. Batteries are DEKA 6TMF, and test good. Any ideas? Thanks

 

[Coug]

Double check with a multimeter at the batteries what the actual output is. Then check again at the generator just to make sure. I'd do it when first started, then again after it's dropped down.

This is just to make sure it's actually a charging issue, and not a wiring issue.

It could be the regulator failing or maybe a bad connection.

 

[Big Tom]

Like said use meter or temporary volt gauge , just to Double check the voltage readings

 

[M998AVAN]

Like said use meter or temporary volt gauge , just to Double check the voltage readings

Will check this afternoon

 

[M998AVAN]

Will check this afternoon

12.4 volts per battery
23.9 volts at generator
Running 1900 rpm 24.6 volts at generator

 

[Action]

12.4 volts per battery
23.9 volts at generator
Running 1900 rpm 24.6 volts at generator

too low

 

[twisted60]

Agree with Action, should be around 28 +/- 0.5 volts coming out of Gen

 

[M998AVAN]

Agree with Action, should be around 28 +/- 0.5 volts coming out of Gen

That’s what I thought, thanks

 

[twisted60]

Amazing things can be found in the TM's.

 

[Ferroequinologist]

Dropping voltage after warming up is almost a sure sign of pending regulator failure. I have an entire pile of alternators, most just needing bearings, some regulators. Maybe one day I will start rebuilding them all, especially with how expensive they seem to be getting.

 

[Bulldogger]

Does sound like a regulator. I had the end plate type on my 60A. It wasn't hard to replace and I did it without removing the alt from the motor. DO DISCONNECT THE BATTERIES FIRST, if you decide to replace the regulator. BUT you should definitely double check all wires, including the exterior post on the other side of the + battery block under the seat (meaning that post is on the other side of the post you see in the battery box). Mine was loose back when I resurrected my Gov Planet purchase.
BDGR

 

[Mogman]

Dump the 60A and invest in a 200A You will be much happier in the long run, I am!!

 

[M998AVAN]

thanks all for the advice. I installed another new 60 amp, and same thing.

 

[osteo16]

thanks all for the advice. I installed another new 60 amp, and same thing.

Well that makes no sense.. Unless both your new and old generator have the same problem... Im thinking bad indicator. Doesnt make sense. Pull it and test resitance.

 

[Ferroequinologist]

Well that makes no sense.. Unless both your new and old generator have the same problem... Im thinking bad indicator. Doesnt make sense. Pull it and test resitance.

He said he checked it with a meter before, so he wasn't just relying on the gauge.

Try running a separate 'sensing' wire (the small one) directly to the battery + and see what your voltages are then. If it goes up to 27-29 volts, you have a bad connection in that circuit running to the alt. Also, measure the voltage at the lug on the alternator, and at the batteries. A significant difference would be a bad connection or corroded cables.

Of course, there is always the slim chance you got two bum alternators...

 

[Retiredwarhorses]

1991 HMMWV, 6.2 L, 60 amp generator. Purchased HMMWV noticed bad rattle noise from generator, after inspection mounting ear was broken (someone forgot the spacer). Charging was still good, stayed in the middle green. I purchased a new one from KASCAR and installed with spacer, charging again stayin the middle green. Got In the other day, the more I drove the gauge would slowly drop to mid yellow. I could stop for a few minutes, start it back up and charging would be good, then slowly drop again. Batteries are DEKA 6TMF, and test good. Any ideas? Thanks

run long test wore leads from your batteries to the driversside...connect to your multi meter and go drive, see what’s exactly going on.

 

[M998AVAN]

I got it out and ran with the new generator 10/15 miles, gauge in yellow to begin with. Then jumped to green. Been good the last couple of days. We will see what happens. Wires seem to be all good. Took all battery cables lose and cleaned as well.

 

[M998AVAN]

I also installed a KASCAR grounding kit, while doing that I noticed diesel fuel ponded up on top of engine block? See picture. Any suggestions on where to start looking for the problem??

 

[DREDnot]

Any suggestions on where to start looking for the problem??

Start with the rubber fuel lines that run across the valley. To filter from lift pump...from filter to injection pump...and the fuel return on top of the injection pump.

 

[HoveringHMMWV]

I also installed a KASCAR grounding kit, while doing that I noticed diesel fuel ponded up on top of engine block? See picture. Any suggestions on where to start looking for the problem??

Mine had the same symptom.

Fuel Leak In the Valley

I returned from a casual 45 minute drive today and noticed a puddle of fuel after parking. After raising the hood and removing the doghouse, I noticed the valley of the 6.5L NA GEP was wet with fuel and the puddle was under the oil filter. I had recently changed the injector bypass hoses and...

www.steelsoldiers.com

-HoveringHMMWV