6Volt charging system

[Biscuit]

Alright all of you old dogs, it's been a while since I've been on the cite but I need your wealth of knowledge. School, work and deployments have kept me busy but I'm at my wits end with my Cub's charging system. My '56 always had charging problems while it was at our farm in OH. When I got it to SC I used the troubleshooting tree many of you have provided and narrowed it down to a bad VR. That fixed the problem for almost 3 years and then it started acting up again. I shot it down to another bad VR and bought one from TSC. Again, it worked well for a while but this year I noticed my amp meter stays on the discharge side while I'm mowing. I keep the battery on a charger/tender so it always starts fine but steady discharging while in operation. When I check the batt while running the voltage readings are all over the place. Good ground at the batt and VR. I used the tree again and when I got to the step of connecting a jumper from the "F" to "Gen" on the VR the wire got very warm so couldn't go any further. I'm suspecting another bad VR, and since it was a cheapy from TSC that is probably the problem. Any chance I have a bad gen burning up VRs? Is the erratic reading at the batt while running an indication of a particular part going bad? Thanks for any help.

[Scrivet]

.... Is the erratic reading at the batt while running an indication of a particular part going bad? Thanks for any help.

Is this a digital volt meter by any chance? Much to sensitive to electrical noise (generator brush induced not a loud radio )to give an accurate reading. If you have an analog meter (one with a needle) it will smooth out the flucations and give you an accurate reading.

I would take the cover off the voltage regulator and make sure both sets of points aren't stuck, burnt, or pitted.

[Biscuit]

Thanks and yes it is a digital. Not sure if I still have my old analog but I'll take your advice and see if I can dig it up. I thought about opening up the VR but didn't have access to a breakdown so I wasn't even sure what I was looking for. Is the VR repairable in any way or is it pretty much garbage when it goes bad?

[bythepond88]

I had a problem with VRs not lasting more than a few years myself (didn't seem to matter whether it was the expensive or cheap one). Finally came across a shop manual for them and decided to try to fix it. The air gaps were wrong, so Iadjusted them, and it worked. Being a pack rat frugal, I had saved the ones I took off, so I took the one that was on the tractor when I was given her (which looks to be original) and reset the point gaps on that one, swapped it in, and its been working for four or five years now. Never got a round tuit to try the third one that I still have on the shelf, but I suspect that I could cure that one, too.

[Mike in Louisiana]

When you do the jumper wire YOU JUST MAKE IT SPARK DO NOT KEEP THE WIRE ON TERMINALS.

[Biscuit]

This morning a took a printed copy of the "Troubleshooting Schematic" to the barn with me and started from the beginning again. I checked the volts on the batt without the tractor running and it was 6.35. When I got to step 3 of the tree , jumping the FLD on the VR terminal to GND, the amp meter on the tractor pegged hard right. I checked the volts again at the batt while it was running (couldn't find my analog so had to use the digital) the volts were jumping around and would peg around 12.8. After cutting off the tractor I checked the batt volts and they had gone up to 6.75. Opened up the VR and no points are sticking and don't look burnt. I'm going to emery the points on the VR and put it back in so I can mow today. Probably order a VR from TM.

[John *.?-!.* cub owner]

Make sure the ammeter has a good ground.

[birddog]

Biscuit; Here are a couple of threads that may help you. They aren't perfect as they don't give exact specs., especially for regulator adjustments. The second and third links are the same tests, just different formats.

http://www.farmallcub.com/phpBB2/viewtopic.php?f=140&t=80345

http://www.farmallcub.com/phpBB2/viewtopic.php?f=140&t=80347

http://www.farmallcub.com/phpBB2/viewtopic.php?f=140&t=80346

[John *.?-!.* cub owner]

Make sure the ammeter has a good ground.

Meant to say regulator.