Farmall C charging system- blown fuse for lights

I don't have teh tractor in front of me and can't picture how the wiring is on it to save my life. If the fuse is blown, will the tractor not charge?

I just remembered that the fuse was blown, and was thinking of heading over to work on it this weekend. It's driving me nuts, though to think that it might not be charging because of a blown fuse. However... I can't remember if the fuse is just for the lights or if it also protects the charging system.


If anyone has a wiring diagram handy, or knows this off the top of their head, it would be appreciated.

Thanks,
John

As far as I know the fuse just protects the light curcuit and has nothing to do with it charging.

John -

Presuming it's wired correctly - not a certaintly on a 60+ year old tractor(!) - the fuse protects only the light circuit. So a blown fuse has no effect on charging system operation.

Bob & Teddy,

Thanks for the super fast replies. I guess this means I am not loosing my mind. Although, when you are thinking about working on something that consumes all your other thoughts to the point of obsession, you tend to over think things and put strange ideas in your own head.

I will have to go over all the wiring on the tractor, regardless. It's all original cloth/laquered wiring and I am pretty sure that it wasn't charging when I had it running.

The biggest problem I have with it is now that it has new rings and what-not, it has 132 PSI compression in all cylinders. The 6 volt battery won't turn the engine over fast enough to start it. I double checked the valve timing and all that, and it's all correct. I am guessing that either the battery has seen better days, the wiring has massive internal resistance, or ??

things I have done/eliminated:
-bearing clearance
-rebuilt the starter
-verified good ground from the starter to battery
-stood on one foot and did a voodoo chant while cranking it over


All that has no effect. I think I just need to get it broke in some. Maybe plow a few acres if we get a week of decent weather...

John - Before you get too deep into the charging issue make sure the ammeter is not stuck. Ie that the charging system is working but not showing on the ammeter. (It happens a lot!). Take a small magnet and bring it close to the ammeter face. If the ammeter pointer is free the magnet will cause it to deflect one way or the other from center as you move the magnet around.

----

Regarding your slow cranking issue it's likely a combination of a tight engine, a tired battery, a bit of excessive resistance in the battery cables (especially where they fasten to the terminals/battery post clamps) etc.

You might also try pull starting the tractor once and letting the engine run a while to seat the rings and loosen the engine a bit.

Oh....and do your voodoo chant again. But this time stand on your head and make sure your nosey neighbor gossip is watching(!)

Good luck!

John - Before you get too deep into the charging issue make sure the ammeter is not stuck. Ie that the charging system is working but not showing on the ammeter. (It happens a lot!). Take a small magnet and bring it close to the ammeter face. If the ammeter pointer is free the magnet will cause it to deflect one way or the other from center as you move the magnet around.

----

Regarding your slow cranking issue it's likely a combination of a tight engine, a tired battery, a bit of excessive resistance in the battery cables (especially where they fasten to the terminals/battery post clamps) etc.

You might also try pull starting the tractor once and letting the engine run a while to seat the rings and loosen the engine a bit.

Oh....and do your voodoo chant again. But this time stand on your head and make sure your nosey neighbor gossip is watching(!)

Good luck!

Bob,
Thanks for the reply.

I remember seeing the ammeter deflect when I lit up the ignition. It's 50 degrees today and was in the teens during the weekend and will drop below 30 tomorrow. Wishful thinking about getting a chance to work on the tractor has got my brain doing flips.

I'll be sure to take my DVOM with me if I get a chance to go work on it tonight. I should also bring the battery back here and charge it up. The last time I was messing with it, I put the voltmeter on it and it only registered 6.3 volts at rest. I know that it drew down pretty good when cranking. I want to say it dropped below 4.5 volts. I can't remember exactly, but I think that it should show a little more voltage than that. I have a 2 amp digital charger, and a regular 2 amp trickle charger. I should put it on regualr trickle charger, just to be sure it is not cutting off the charge before the battery is completely charged.

The battery shipping date was Dec-2007 and I think I have had it for 8 months, but it hasn't been used at all. I charged it up, initially, then it sat without being charged for probably 2 days. I am not sure how much charge it lost and I didn't test teh voltage at rest after I had charged it. I charged it with a newer shumacher digital charger on a 2 amp setting, until the charger said it was fully charged. This battery could have gone bad from sitting too long without being cycled or charged. IIRC, lead/acid batteries loose about 1% of their charge per day, if they are not charged. So, in 100 days, or 3 months and 10 days, the battery would have been completely dead. Whether or not letting it sit for 8 months had permanent affects, I couldn't tell you. I have had hi- and-miss luck with batteries, so I couldn't say for sure.


Thanks again,
John

John - A healthy, fully-charged lead-acid battery runs down very slowly - typically 10 - 15% a month. So presuming it was fully charged when you left it, your year-old battery should still have better than half its charge left after sitting idle 3-1/2 months - more than enough to crank up your C.

FWIW my old Minnie-Mo (2 year old 6 volt battery) sat idle from mid-August until Thanksgiving. Yet it cranked smartly and started right up without assistance on Thanksgiving day.