Barrman
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4 1/2 years ago I wrote about my ALT 2 issues:
http://www.steelsoldiers.com/showthread.php?54292-CUCV-alternator-symptoms-diagnosis-and-fix
From then until now, the ALT 1 light would kind of glow anytime anything electrical was turned on. Running the lights during the day I couldn't see the glow, but could at night. Very dim glow with just one thing turned on. Having the lights, heater and wipers on made it brighter.
I cleaned every ground wire I could find under the hood, under the dash and anywhere I thought they might be hiding. No change. I pulled apart the firewall electrical plug and cleaned it. No help. Swapping the alternator relays did nothing. Neither did messing with the fuses or changing out volt meters. I always had 14.2-14.4 volts on ALT 1 with all the other stuff on.
So, I just ignored it. Maybe the M1009 was haunted or something?
All these years later I finally figured it out. I was driving to town Sunday afternoon and hit a bump. The ALT 1 light glowed full bright and then went out. I looked at the gauge and all was right, so I kept driving. Another bump and full bright again. I was ready at the rail road tracks and watched the gauge with the light in my periphial vision. Light on, gauge steady. Hmmmmm.
I got where I was going and left the engine on. Raising the hood showed no smells or obvious out of place wires. I touched the big red power in wire for ALT 1 and got a huge shower of sparks inside ALT 1. Found the problem! I turned it off and touched the wire again. The entire post was loose and anytime it moved, it touched the case and caused sparks.
I still had a meeting to attend and a drive home, so I left it alone and went home slow. I didn't actually pull up the TM's on my ipad during the meeting, (Everybody does have all the TM's on their phone and ipad, right? Maybe just me.) But I did think about it and was pretty sure the input post had a nut on the inside. This could be a pull it, pull it apart, tighten a nut and put it all back together kind of thing. Easy and cheap.
It wasn't. I got it apart before work Monday to find what the manual calls a "connector" or what looks like to me as a piece of thin flat metal between the power in post and the rectifier burned away. Just part of the jagged edge was touching part of the nut holding the post in.
Still easy enough after looking up the part:
http://www.aspwholesale.com/index.php?act=viewProd&productId=7152
Cheap too until I saw the $10 minimum order policy. I bought a complete kit since the alternator was off and already apart.
However, I needed to drive the truck on Tuesday. I didn't need to drive the M715 which has the exact same engine and wiring set up. I didn't even consider taking an alternator off RED. Colton would not find any humor in that. I pulled ALT 1 from the M715 and bolted it up to the M1009. 14.4 volts and all good.
The next morning I fired up in the dark and hit the lights. No glow from the ALT 1 light. I turned on the wipers, no glow. I turned on the heater fan to high, no glow. I turned on the a/c to high, no glow. The gauge was still smack dab in the middle of the green with all that stuff on too.
To sum up. CUCV's are not haunted. If an ALT light is glowing, something really is wrong. The only thing I didn't check was the inside of the alternator and that is what it was. I would hate for somebody else that has a weak glow to find issue in the middle of nowhere on a cold and dark rainy night because I didn't bring this up. I hope this helps somebody.
http://www.steelsoldiers.com/showthread.php?54292-CUCV-alternator-symptoms-diagnosis-and-fix
From then until now, the ALT 1 light would kind of glow anytime anything electrical was turned on. Running the lights during the day I couldn't see the glow, but could at night. Very dim glow with just one thing turned on. Having the lights, heater and wipers on made it brighter.
I cleaned every ground wire I could find under the hood, under the dash and anywhere I thought they might be hiding. No change. I pulled apart the firewall electrical plug and cleaned it. No help. Swapping the alternator relays did nothing. Neither did messing with the fuses or changing out volt meters. I always had 14.2-14.4 volts on ALT 1 with all the other stuff on.
So, I just ignored it. Maybe the M1009 was haunted or something?
All these years later I finally figured it out. I was driving to town Sunday afternoon and hit a bump. The ALT 1 light glowed full bright and then went out. I looked at the gauge and all was right, so I kept driving. Another bump and full bright again. I was ready at the rail road tracks and watched the gauge with the light in my periphial vision. Light on, gauge steady. Hmmmmm.
I got where I was going and left the engine on. Raising the hood showed no smells or obvious out of place wires. I touched the big red power in wire for ALT 1 and got a huge shower of sparks inside ALT 1. Found the problem! I turned it off and touched the wire again. The entire post was loose and anytime it moved, it touched the case and caused sparks.
I still had a meeting to attend and a drive home, so I left it alone and went home slow. I didn't actually pull up the TM's on my ipad during the meeting, (Everybody does have all the TM's on their phone and ipad, right? Maybe just me.) But I did think about it and was pretty sure the input post had a nut on the inside. This could be a pull it, pull it apart, tighten a nut and put it all back together kind of thing. Easy and cheap.
It wasn't. I got it apart before work Monday to find what the manual calls a "connector" or what looks like to me as a piece of thin flat metal between the power in post and the rectifier burned away. Just part of the jagged edge was touching part of the nut holding the post in.
Still easy enough after looking up the part:
http://www.aspwholesale.com/index.php?act=viewProd&productId=7152
Cheap too until I saw the $10 minimum order policy. I bought a complete kit since the alternator was off and already apart.
However, I needed to drive the truck on Tuesday. I didn't need to drive the M715 which has the exact same engine and wiring set up. I didn't even consider taking an alternator off RED. Colton would not find any humor in that. I pulled ALT 1 from the M715 and bolted it up to the M1009. 14.4 volts and all good.
The next morning I fired up in the dark and hit the lights. No glow from the ALT 1 light. I turned on the wipers, no glow. I turned on the heater fan to high, no glow. I turned on the a/c to high, no glow. The gauge was still smack dab in the middle of the green with all that stuff on too.
To sum up. CUCV's are not haunted. If an ALT light is glowing, something really is wrong. The only thing I didn't check was the inside of the alternator and that is what it was. I would hate for somebody else that has a weak glow to find issue in the middle of nowhere on a cold and dark rainy night because I didn't bring this up. I hope this helps somebody.
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