Burnt Accessories Belts

[sochuck]

Hi guys, My 84 M1009 has been eating the GEN 1 belt. This vehicle is a recent add to my garage. When I picked it up it had a new looking Gen 1 (driver's side) gen, real new looking. SOOOO after the install of the Gates 7575 belt it appeared that the pulleys were out of alignment. I wrote it off as an optical illusion. After the Gates lasted about three days I picked up some new belts from a good friend of mine and installed them. about three days later same thing...So, I looked harder at the alignment and the Gen it self and could see that there was a -2mm difference between the two. To save time and flaming, I replaced the pulley on that unit with one from another, shimmed it out a bit and put a new belt on it. Again it just didn't look right but gave it a go. The new belts has about 200 miles on it and it jumped the pulley on US 68 today and took the other two with it. I managed to unwrap it from the fan and after cussing myself for not having any tools with me managed to get the PS belt on so I could at-least get mobile. A bit more back story...the GEN 1 light would stay off at idle but on accel and at speed it would come on. I also noticed that the Volt Gage would run in the red and would fluctuate as if the regulator from one or both Gens was failing. I think, I hope that is the cause of this is a bad Gen 1 (that was tested and found good) reg causing the gen to load excessively dragging the HE DOUBLE TOOTHPICKS out of the belt leading to premature failure of that belt.

Now I am thinking of dumping that pulley and replace it with a non-Mil-Spec gen and motor on. OR, you can fill the blank in!

Question, how important is it for the amp output of the Gens to match, can a let us say 200 amp non mil-spec be ok as a replacement or not.....



Cheers,

 

[61sleepercab]

SOMETHING HAS TO BE VERY BAD WRONG TO EAT BELTS IN DAYS NOT THOUSANDS OF MILES! Bad alignment will eat belts/throw belts off. Do you have a bad or dying battery that the alternator is trying to charge?.......... Load test battery. Is there a bad regulator overcharging or could you have a dead short somewhere??? Do you have a loner/ different alternator to try? Do you smell battery acid, hot chemical smell under hood when running and parked? (bad regulator or bad battery cell) Are alternator bearings shot/dragging? Hope these tips may help. I replaced a single Lease Nevelle 200 amp alternator with a 85 amp GM one wire alternator with no problem on a retired Ford ambulance. I have always heard to match battery size in multi battery setups but have no info to help you on multiple alternators. Mark

 

[ke5eua]

This reminds me of a hmmwv we had in Iraq. Kept throwing the serp. belt. We replaced every thing there was and it still did it. It ended up being the harmonic balancer causing all the issues. Once we replaced it no more eating of the belts.

Heck, our 1009 in Iraq was a salvage build and only had one belt, the PS. We had to slave it off most of the time, and put the batteries on charge at night. Leave the ignition on when your at the chow hall and you will be looking for a jump. Ask me how I know.

 

[Blake]

My cucv was eating fan belts and a replacement harmonic balancer took care of the problem.

 

[sochuck]

Interesting on the harmonic balance....I will look at it but the there is only one belt that is having issues and that is GEN 1. When running the pulleys do not osculate but I could be wrong on that being an indicator. There are no odd smells, but as I said I can watch the Volt Meter (gage) move into and often stay in the red. If the meter is reading correct that would be over-charging, but.... Back to the harmonic balance r what would I be looking for??


Cheers

 

[Blake]

See if the harmonic balancer is wobbling while engine is running.

 

[Keith_J]

I vote for misalignment. Put a voltmeter on the batteries while running, 13.5 to 14.8 volts.

Check the parts TM to make sure the right parts are on the correct side. This is possible if both alternators were pulled and parts put into a single place.

 

[sochuck]

I vote for misalignment. Put a voltmeter on the batteries while running, 13.5 to 14.8 volts.

Check the parts TM to make sure the right parts are on the correct side. This is possible if both alternators were pulled and parts put into a single place.

I understand the use of the Voltmeter in your statement but as far as the last, are not the Gens interchangeable. There was an obvious swap out of Gen 1 because it looks new, so I can see a possible error there.

 

[Keith_J]

Yes, they are the same alternators but different mounting hardware.

 

[sochuck]

Yes, they are the same alternators but different mounting hardware.

awwwww tracking you now

 

[sochuck]

UPDATE.....replaced Gen 1 with a non Mil-Spec Gen, installed a cheap belt from Advance Auto. Hooked everything back up and fired the Pickle up. No surging on the Volt Meter. Ran for several minutes to allow the belt to seat. Checked belt, so far so good....Drove for a bit stopped checked mail and drove home. Checked the belt a bit of stretch but not allot....Time will tell.....

 

[nyoffroad]

I was going to suggest two things.
#1 the over charge maybe a bad regulater in #1 alt.

#2 The belt wearing out seem like a pully out of line, Not just 'needing a shim' forward, more like the alt. is tilted and causing the belt to wear on one side and get thinner and that allows it to ride lower inthe grooves and then slip. The fix is check for bent mounting brackets.