Charging woes

Electrical issues
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Charging woes


Post by King » Sat Oct 28, 2006 8:17 pm

Description: I seem to have a continuing problem in the charging system on my 51 FL with 32E generator 6 volt system

Hi All

I seem to have a continuing problem in the charging system on my 51 FL with 32E generator 6 volt system. I was not getting much voltage out of the relay and the GEN light was a dull flicker under all conditions so I replaced the original Delco-Remy with an electronic unit. Now I’m getting around 7 volts at the BAT terminal of the relay and over 10 at the Relay terminal of the generator. But across the battery I’m still only getting 6.1V under all conditions off, at idle, and revving. The bike starts well and runs OK but the headlight is a feeble orange beam, and the horn puts out a weak blat so the juice doesn’t seem to be getting past the relay and into the system.
I removed the battery it had plenty of fluid and it read 75% charge (three balls floating on my pocket hydrometer). When I flashed the GEN terminal of the relay it had a good spark so it seems be OK.
I could be wrong, but I think I’ve narrowed the hunt down to either a glitch in the wiring or a bad battery.
Questions are 1. Can I run a jumper wire from the BAT terminal on the relay to the + on the battery as a check on the wiring? and 2. Can a battery have a charge (and accept one from a battery charger) and still be defective ?

Thanks for your responses.


Post by Dereborn on Aug 15, 2006, 4:15pm

King! I'm not an electrical expert, and my tech-english is not very good.... BUT.... I have had ALL the electrical gremlins swarming my pan for several years.. Seriously, about the battery, you must get it "load-tested" or whatever the terminology is in english. You check the VOLTS at home, and you charge the VOLTS with the garage charger, but the AMPs is just another story...
I'm sure someone on this excellent board can tell you better what it's all about, I just wanted to share my experiences ...

I finally converted to 12v this summer, and not only has the headlight stayed on all the time, but i seem to notice a bit more power in the overall performance of the engine as well!
Now the hunt (!) for a magneto is on, I'm gonna put one on this winter...

Good Luck, stay cool!


Post by PanPal on Aug 22, 2006, 12:43am

Last week I was packing for a 3 day trip with the Pan and when I went to leave,my Generator light stayed on. I loaded the bike in my truck and headed to a friends house to take a look. He had me start it still loaded in the truck about 11Pm at night. As luck has it since it was dark we noticed a sparking from a small jumper on top of my regulator. The jumper grounds the regulator since it is rubber strap mounted to the bracket. He pushed the end of the jumper wire and the meter needle went up to 7.2 and my generator light went out.
Odd, but he also turned my ignition switch from headlights on to ignition only and it stayed running. I think this was coincidence however I have been able to switch back and forth without a problem since.

Post by Sidecar on Aug 23, 2006, 1:50pm


Yes to question number two.

Post by pantony on Aug 27, 2006, 3:44pm

King you can get a load tester and have it in your garage for future use for eveything 6 or 12 volts. Get one from I used to work there as a road service man and I had a load tester I always kept in my service truck. I't's not all that expensive and always worked good. The good ones are made by Associated and they are made in the USA. I had banged that thing around for over a year and it never broke. Get a good hydrometer, (not the ones with the little balls) one that tells a specific gravity reading 1.265spg is fully charged, 1.150spg is fully discharged, regardless of what your voltmeters are saying, THEY MEAN NOTHING!!! Only do a load test with a fully charged battery and if you had a shorted cell, that cell will boil under a load. charge your battery a night before you test it and give it about 6 hours to cool down after you charge and before you test it.

Post by 108 on Aug 28, 2006, 12:14am

King, It sounds like you have a lot of resistance someplace . That may be why there is 10V at the gen. - it cant get to the battery. Everthing the guys here have said is correct. Sure it will start , but technically, a battery with 6V is dead! Fully charged is about 6.3-4. You should start out with it fully charged so you dont force the system to charge up a dead battery. The hydrometer only tells you the acid is charged , it may have broblem inside an not even make enough amps to glow a dash light bulb.! If it had a shorted cell it would probably run its self down to nothing in a day or less. Bypass that regulator with a jumper after its started and see if thing improve. For a quick load test if you cant get a tester , just hook up a headlight bulb to the charged battery, if it stays bright for a half hour its probably ok

Post by pantony on Aug 28, 2006, 5:56am

hook up a cigarette lighter if you can get one from a boneyard for a quick load test

Post by King on Aug 30, 2006, 6:39am

Thanks Guys

Great advice. From what you have said I'm pretty sure its the battery. I'm about as far from my Pan as i can get right now in Indonesia but will be home soon to check it out as you have suggested. Will post results

Good rides


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