servicing starter motor
- Thread starter marshall
- Start date
I installed the new switch and bench tested that when its pushed in all the way the motor spins. In the pictures the open section of the body had some kind of wrapping tape or cloth that disintegrated.
Looking in therer you see its pretty grubby. I've tried loosening the two screws on the sides and they don't budge. So getting it apart doesn't look like something I'm going to be able to do without the risk of messing up the heads of the screws. So I'm thinking the best thing to do is install it in the tractor and if it works well, no need to go service what isn't a problem now. There's a metal band that goes over this open section but I'm just wondering what I should wrap it with prior to the band going on. Some kind of tape or cloth?
Looking in therer you see its pretty grubby. I've tried loosening the two screws on the sides and they don't budge. So getting it apart doesn't look like something I'm going to be able to do without the risk of messing up the heads of the screws. So I'm thinking the best thing to do is install it in the tractor and if it works well, no need to go service what isn't a problem now. There's a metal band that goes over this open section but I'm just wondering what I should wrap it with prior to the band going on. Some kind of tape or cloth?
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staninlowerAL
501 Club
The disintegrating material that you found is probably the fields insulation material. The OEM material was cloth type fabric and has probably decayed with age. The two screws that you referenced hold the fields in place inside the housing and are probably rusted in place. If you are not going to remove the fields to upgrade the insulation there is no need to take them out so long as there is no electrical problems. Replacing the brushes and bearing/bushing and cleaning it up internally would probably extend the life of the starter. It's hard to tell how much the brushes are worn from the picture but they should extend through the holders about 1/4-3/8 inch and are not very expensive. The original cover over the opening under the band was made from something like oil impregnated, thin stencil board but now days most shops just wrap it with 2 inch duct tape and install the metal band over the tape. It helps to protect it and keep the moisture out. JMHO Stan
Hi,
The starter is held together by 2 long bolts going through it. The small heads for them are on the end of the starter. The big screws on the sides of it don't hold it together, and aren't removed to take it apart.
If you don't want to take it apart, I would have the starter rebuilt if it needs it. The starter needs cleaning inside.
If the bushings are worn, the armature can rub inside the starter, usually that makes the starter run slower.
Below is a page from the Cub and LoBoy parts manual showing the 6 volt starter.
https://farmallcub.club/rudi/farmallcub.com/rudi_cub/www.cleancomputes.com/Cub/Cub Parts Manuals/TC-37F Revision 3/Group 08 - Electrical/Page 08-10.jpg
Below is a picture of part of the armature, you can see the rub marks on the large part of it. The end with the gear is down. The surface where the brushes run should be clean and flat, and copper colored. Clean it if it is dirty so the brushes make good contact.
If you take it apart, the manual says to put oil in the bushings. The bushing at the end with the gear can be oiled without taking the starter apart.
The starter is held together by 2 long bolts going through it. The small heads for them are on the end of the starter. The big screws on the sides of it don't hold it together, and aren't removed to take it apart.
If you don't want to take it apart, I would have the starter rebuilt if it needs it. The starter needs cleaning inside.
If the bushings are worn, the armature can rub inside the starter, usually that makes the starter run slower.
Below is a page from the Cub and LoBoy parts manual showing the 6 volt starter.
https://farmallcub.club/rudi/farmallcub.com/rudi_cub/www.cleancomputes.com/Cub/Cub Parts Manuals/TC-37F Revision 3/Group 08 - Electrical/Page 08-10.jpg
Below is a picture of part of the armature, you can see the rub marks on the large part of it. The end with the gear is down. The surface where the brushes run should be clean and flat, and copper colored. Clean it if it is dirty so the brushes make good contact.
If you take it apart, the manual says to put oil in the bushings. The bushing at the end with the gear can be oiled without taking the starter apart.
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After bench test of the starter and seeing that it spun nicely with the new switch + 12v, I put it on the tractor and found that its still not starting and there is no sound of activity in the starter.
I trickle charged the battery, made new connections from its terminals to ground and to the starter. I tested with a multimeter that 12 volts are getting to the starter (leads on the case of the starter and to its switch terminal). Any other ideas about what could be wrong that there'd be zero sign of life when I pull the starter lever?
I trickle charged the battery, made new connections from its terminals to ground and to the starter. I tested with a multimeter that 12 volts are getting to the starter (leads on the case of the starter and to its switch terminal). Any other ideas about what could be wrong that there'd be zero sign of life when I pull the starter lever?
Dale Finch
501 Club
Ditto! Those mating surfaces are your ground connection back to the battery.
They should be nice and shiny with no paint or rust.
Try using a pair of jumper cables. Connect one cable directly to the ground terminal of your battery and to a bolt that holds the starter in place. Connect the other cable directly to the hot terminal of your battery and the other end to the lug on the switch on the starter. Pull the starter rod and see if it will turn over.
This indeed revealed that the starter immediately sprang to life with the jumper cables. Oddly, after a good amount of cranking there is no sign of the tractor starting. So I've definitely got a problem getting voltage to the starter. "Cleaning the mating surface between starter and torque tube"? I'll shine all contact surfaces with a fine sandpaper or a file and get everything shiny and will buy new battery cables if I have to, but given that it doesn't start with the jumper cables I'm wondering if perhaps I didn't install the starter back on the tractor correctly. Is there some way that it needs to mesh up with the gears inside the case that it inserts into? Is it possible that its spinning but not causing the engine to turn?
staninlowerAL
501 Club
When the starter is cranking does the fan blades at the radiator spin? If the engine is cranking over and no indication starting then the next step is to ensure that you have spark at the plugs, fuel flow to the engine cylinders and unrestricted air flow through the breather. If all these check OK then next is check the timing. The Basics: Fuel+spark+airflow all at the right amount/time and place=ignition. JMHO Stan
As stated, the fan blades will tell if the engine is turning. If the engine is turning but not starting you have a separate problem. Let's fix them one at a time. Repeat the jumper cable test only using 1 jumper. Connect it from the battery hot terminal to the starter switch. If it turns over, you have a problem with the cable/connections on the hot side. Connect it from the battery ground lug to the starter mounting bolt. If it turns over, you have a ground problem. Clean the connections and replace the cable as needed.
Once it turns over reliably, look into the starting problem. (If your starting problem is due to lack of spark, the cranking fix may take care of it.)
Maybe a silly question, but when you hooked the battery cable to the starter, was the switch on? Starter will turn over with the switch in the off position. That may be why tractor didn’t start. And to repeat an old saying, make sure to shake hands with the gear shifter anytime the starter or hand crank are used. I know from experience and no longer take it for granted
Matt Kirsch
501 Club
Unfortunately a voltmeter will "lie" to you in this situation. I'd bet if you left the voltmeter connected and hit the starter button the voltage would go to zero. That's the indication of a high-resistance connection. Look at the condition of the underlying wire. If it's green or black, it won't matter how shiny you get the terminals.
The starter itself is "good enough" that you don't need to worry about it for this particular issue. It might not be perfect but it's far from needing service.
The starter itself is "good enough" that you don't need to worry about it for this particular issue. It might not be perfect but it's far from needing service.
Thanks Jim Becker for the simple final troubleshooting steps.. I quickly identified the ground as being at fault. This was a cable I bought about 3 years ago so I thought there was no way this one was the problem. But
after stripping back to some fresh copper and reconnecting, the fan was turning and I just needed to increase the gas in the tank so that it fired right up. This is the second time I've seen that oxidized copper is not a conductor. I guess I've learned me lesson now. I wish this tractor didn't leak so much gas. I can't leave it for a month with a gallon of gas in the tank because it will be pretty much empty after 4 weeks. I've never found the source of the leak. I probably need a new tank.
Thanks all, for sticking with me on this one. I bought this tractor from an old farmer in 2013 and in the first week it sounded like it was seizing up and died in my back field. I was convinced I just wasted $1500 on a new piece of iron sculpture I'd have to pay to get hauled away, but someone on here told me to put a little oil in the fan hub and I was back to work. Despite all my worries about the internet's bad effect on the world, this little forum continues to be a powerful place for strictly positive, helpful interaction. Til, my next breakdown.... which is always much sooner than I'd like... thanks again!....
after stripping back to some fresh copper and reconnecting, the fan was turning and I just needed to increase the gas in the tank so that it fired right up. This is the second time I've seen that oxidized copper is not a conductor. I guess I've learned me lesson now. I wish this tractor didn't leak so much gas. I can't leave it for a month with a gallon of gas in the tank because it will be pretty much empty after 4 weeks. I've never found the source of the leak. I probably need a new tank.
Thanks all, for sticking with me on this one. I bought this tractor from an old farmer in 2013 and in the first week it sounded like it was seizing up and died in my back field. I was convinced I just wasted $1500 on a new piece of iron sculpture I'd have to pay to get hauled away, but someone on here told me to put a little oil in the fan hub and I was back to work. Despite all my worries about the internet's bad effect on the world, this little forum continues to be a powerful place for strictly positive, helpful interaction. Til, my next breakdown.... which is always much sooner than I'd like... thanks again!....
Thanks for posting what the problem was. As far as leaking gas, I think it would be far more likely that the leak is from the sediment bowl unless your tank has severe rusting and pin holes. Try and isolate where the leak is before you look for another tank. You could line your tank if you found that to be the problem.
Don McCombs
501 Club
Do you shut the fuel off at the fuel strainer bowl when not in use? Do you find fuel on the floor or the ground during periods of non-use?
If the gas tank on a Cub leaked, you would probably see gas on the Touch Control, or the clutch housing, unless it was leaking along the right or left edges.
Gas can drip from the IH carburetor, from the drip hole on the bottom of it. The drip hole is there to let any excess gas out, onto the ground. Nothing should be dripping from the hole.
If it is dripping there when sitting, dirt in the carb needle and seat can cause it, or the needle and seat worn, or the float level too high.
I would put a metal pan under the carb when the Cub is sitting, and see if it is dripping.
If it is dripping much, you can save the gas and use it.
Below is a picture from TM Tractor Parts of the bottom of the IH carb, showing the drip hole. The hole is to the left of the drain plug.
