Electrical Problem on Farmall H

Wed Jul 13, 2005 10:15 am

I am working on an H which hasn't run in a year of so. I am getting plenty of fuel to the plugs but no spark. It has been converted to 12 volts. I am working my way throught the system cleaning connections. When I removed the external coil, I found that the contact for the mag wire has a screw head. There is a lot of rust there and I would like to remove the contact (screw) so that I can clean it up properly. My questions: Is there a fluid inside the coil ? If so, will it be O.K. to remove the screw for cleaning if I set the coil upright so there can be no leakage? Will removing the screw damage the coil? Thanks, Dan

Wed Jul 13, 2005 10:20 am

Dan, removing the screw should pose no problem.

Wed Jul 13, 2005 10:59 am

Thanks, BD. Dan

Ballast Resistor Problesm

Thu Jul 14, 2005 10:55 am

Some additional progress and one remaining problem on the electrical system of the H. I had noticed that the wire in the ballast resistor was defective yesterday and had replaced it with a new one from an auto parts store. After reinstalling coil this morning I still got no spark. I found that the wires were hot to the switch but not from the switch to the resistor. I installed a new wire in that segment, hit the starter and it fired up immediately. That is good. Now the bad. Smoke was coming from the new resistor so I shut it down quickly. I called the shop which did the original change over from six to twelve volts. The conversion was done 8-10 years ago and they didn't know what resistor they had put in. They suggested that I bring the alternator in and let them check for over-charging. I will do that but, if this is not the problem, can anyone provide info on what amperage the ballast resistor should have. Your suggestions will be appreciated. Dan

Thu Jul 14, 2005 11:21 am

A ballast resistor will normally run fairly hot. That is why they are typically mounted in a ceramic carrier. How much smoke and for how long? It may just have a little oil on it that needs to burn off. If it is just a little wisp, a couple minutes wouldn't be disturbing.

Thu Jul 14, 2005 12:37 pm

Jim is right, ballast resistors typically run very hot as they are dissapating a lot of energy. If you have a voltmeter, you can at least run it long enough to measure the output voltage from the alternator. If it is around 14 volts plus or minus a bit then let it run and watch the wiring. In this circuit loop all you have is the coil and the ballast resistor grounding through the points. Unless the alternator output is high enough to significantly increase circuit current most likely the worst that could happen is that the ballast resistor will burn out as it is the weak link in the circuit.

Thu Jul 14, 2005 1:56 pm

After getting Jim's message on the ballast smoking as the oil coating burned off I went back out and started the H again. I let it run close to 10 minutes, sufficient time, I would think, for wiring or ballast to malfunction if they were going to. It was running smoothly, showing about 60 lbs.of oil pressure when I shut it down. There may be an alternator problem. Just before I shut it down, I noticed that it had pegged out on charge side. So I will probably take the alternator in to be checked. Again, this tractor has not run in a couple of years and there was serious grinding of gears when I attempted to put it in gear. Maybe just needs an adjustment, may be more serious. I will tackle that problem soon. Once again, I want to express my appreciation for the support which is provided on this forum. My knowledge of mechanics, as well as my aptitude for mechanical repair, lie somewhere on the negative side of zero. Yet I have been able to make many repairs on the H, the SA, and the cubs, repairs which I would not attempt without the support of forum members. BD, John and Jim gave that support this time but many others have helped on previous repairs. I thank all of you. Dan

Thu Jul 14, 2005 3:54 pm

A pegged ammeter may not indicate a serious problem either, at least not if the battery is somewhat discharged. Most alternators can put out 60 or more amps. If you still have the original ammeter, it is probably only 20 amps. An alternator can easily peg it or ruin it with excessive current.

Thu Jul 14, 2005 7:01 pm

Dan England wrote: Again, this tractor has not run in a couple of years and there was serious grinding of gears when I attempted to put it in gear.

Since you say attempted, I assume that you were unable to get it into gear.

My Massey Harris sat in a damp shed for a few years after Dad died. During that time the clutch disk rusted fast. Perhaps that has happened to your clutch. My brother fixed it, but he and the tractor were in Ohio and I was in Kansas, so I don't know how he did it.


Thu Jul 14, 2005 8:03 pm

Ike: I attempted to put it in gear but decided it would not be wise to force it. I think it might have chipped teeth on the gear had I done so. Dan

Thu Jul 14, 2005 8:17 pm

Ike: When you talk with your brother would you ask how he corrected the problem. I suspect that I will be asking forum members about the clutch soon. Thanks, Dan

Thu Jul 14, 2005 9:14 pm

Dan can you get it in gear with the engine stopped? How aboput rocking it a bit? If you can start it in gear it may loosen up driving around. Notice I say may. No gurantee.
Few years back, helped my friend Al cobb. We changed out a rear end on a hay truck that had layed out 6 months in the cement making area around Nazareth PA. All the farmers in that area keep machinery in closed sheds. It was a big GMC with a peak. Clutch froze to the fly wheel. Horsed it in to 1st and drove it 200 miles home to Geneva NY. Drove another 10, 000 or so miles like that the clutch never did let go. Always figured it would let go, never did.


Fri Jul 15, 2005 5:33 am

Beaconlight: I didn't try putting it in gear before starting the motor. I will give that a try this weekend and let you know the results. Dan

Fri Jul 15, 2005 6:21 am

Beaconlight: After giving your question some thought, I believe that I can put it in gear and change gears when the motor isn't running. The gearshift is not binding, it moves freely. It is just that the internal gears don't stop when out of gear or when the clutch is pressed down, thus the grinding noise when I try to enter a gear. The tractor is at my son's place but I will try to go out today and check it out. Thanks for the suggestion. Dan

Fri Jul 15, 2005 8:00 am

Just make sure you have a lot of room around the tractor when you try it.