fusible link keeps blowing

[meatloaf]

YOu should not see 28 volts at your Alt on GAS engine....12 volt setup.

Do you have anyone you can swap out alternators with...for test purposes?

Agree on the voltage spike... I found the old alt my 60 had prior to the swap. I cannot remember if was good or not...

Funny thing though. this afternoon I started my brother's truck and could not duplicate the voltage spike... I used a jumper instead of fuses and I revved up the engine multiple times in a 20-30 minute span, the highest voltage I got was 14.1V at high rpm's, lights on. wiggled wires under/around the dash, steering, etc., and it was still fine. put the dash back, still fine. took it out for another 30 drive with lights on with me following behind just in case, still fine.

One thing i did notice, which may be unrelated, is that when he would engage his blinker to turn, both the back up lights, the brake and rear side-marker lights, would also flash at an offset rate from the blinker. The backups were very dim when doing this while the brake/side-marker illuminate normally.

Thanks,
ML

 

[mmw68]

Meatloaf,
I have a 2F alt you can use for troubleshooting if you need it. -Mark

 

[meatloaf]

Meatloaf,
I have a 2F alt you can use for troubleshooting if you need it. -Mark

Thanks Mark,

I will get back with you if the fuse blows again.

Luis

 

[haryv]

Sounds like a defective voltage regulator sending to much current to the armature. Never in my life seen a voltage this high on a alternator. But also, I have never run a alternator that is not connected to the battery. I wonder if there is a temp partial open causing a voltage spike to occur? Interesting thread indeed. Check battery cells to make sure they are full.

 

[Elbert]

Do teh older model 60's have external regulators?

 

[meatloaf]

Sounds like a defective voltage regulator sending to much current to the armature. Never in my life seen a voltage this high on a alternator. But also, I have never run a alternator that is not connected to the battery. I wonder if there is a temp partial open causing a voltage spike to occur? Interesting thread indeed. Check battery cells to make sure they are full.

I will check the battery cells,,,

Do teh older model 60's have external regulators?

Not sure about the older sixty's but this this one does have the external reg.

 

[meatloaf]

Sounds like a defective voltage regulator sending to much current to the armature. Never in my life seen a voltage this high on a alternator. But also, I have never run a alternator that is not connected to the battery. I wonder if there is a temp partial open causing a voltage spike to occur? Interesting thread indeed. Check battery cells to make sure they are full.

Haryv,

What do you mean by temp partial open? Do you mean like a temporary partial open on some wire? Battery (sealed OPtima Redtop) checked out good at Oreilly's, they charged it overnight. We ran the lights and flashers for less than one hour and the battery was dead. I think it is bad, but not the cause of the voltage spikes. Measured again and voltage peaked 25.3V when it blew the fuse.

This thing has me stumped! Help!