Cub starter question

[Paul 300 U]

Hello. I have a 1961 Cub I bought it a few months ago. The starter didn't work, it came with hand crank! Fortunately it's pretty easy to start with the crank but I'd like to get the starter working properly. Today I removed the starter. All in all it looked pretty good I thought. I'm not 100% on what I'm looking at but it appears the brushes are in tact and making contact. The wires are all connected. The armature looks ok but I cleaned it up a bit. After I cleaned it and reassembled I bench tested using a 6 volt battery and jumper cables attached to the stud on the starter and to the starter housing and nothing happens. What steps can I take to try and repair? It's my first time through one of these. Thanks as always. Paul

 

[caterpillar guy]

I would start by under cutting that commutator where the brushes ride. Look at the connection under that saddle switch on the side of the starter where the cables connect to. It should come off with those 2 screws. I would suspect the contacts there are burned from arking. I would also probably just add some brass to the switch contacts if they are burnedby melting it on like you would braze to build them up then fit it accordingly so both contacts can make connection. Clean all wires and connections at the starter and it will probably work fine.

 

[Fritz Maurer]

Based on what you have stated so far it sounds like you have an open field winding. But to be sure, pick yourself up an IT manual for your tractor… they open up electrical components and outline some simple tests with a test light.

 

[560Dennis]

Need test the armature on growler for short. Or with a volt ohm (3 test) and test field coils for ground .


From the photo of the armature , the commutator will need to be turned on a lathe to clean away the uneven wear. Then the mica insulation between the copper armature bars need to be under cut to serpar them . Do you have a lathe?

 

[grandpa Love]

Hello. I have a 1961 Cub I bought it a few months ago. The starter didn't work, it came with hand crank! Fortunately it's pretty easy to start with the crank but I'd like to get the starter working properly. Today I removed the starter. All in all it looked pretty good I thought. I'm not 100% on what I'm looking at but it appears the brushes are in tact and making contact. The wires are all connected. The armature looks ok but I cleaned it up a bit. After I cleaned it and reassembled I bench tested using a 6 volt battery and jumper cables attached to the stud on the starter and to the starter housing and nothing happens. What steps can I take to try and repair? It's my first time through one of these. Thanks as always. Paul

I have bought several used, good,original starters from JP tractor........ As for fixing yours, I don't have a clue, my wife repairs our starters, generators, carbs.......

 

[used red MN]

I would start by under cutting that commutator where the brushes ride. Look at the connection under that saddle switch on the side of the starter where the cables connect to. It should come off with those 2 screws. I would suspect the contacts there are burned from arking. I would also probably just add some brass to the switch contacts if they are burnedby melting it on like you would braze to build them up then fit it accordingly so both contacts can make connection. Clean all wires and connections at the starter and it will probably work fine.

First off very few people have the machinery to “undercut” an commutator of an armature. That means to groove out the insulation between the copper segments. This is not that critical on a starter. It is far more beneficial when the armature is being used in a generator. People are going to cringe, but I was shown this trick by an old mechanic. Place the armature in a drill press by clamping the shaft that sticks out past the commutator in the chuck. Run it on a slow speed and stroke a sharp file on the commutator. Be careful to stay away from the step-up on the segments that lead up to a bigger diameter to where the windings attach. Finish it with some 180 grit or finer emery tape. You can also do this with a hand drill but most only have a 1/2” chuck so you have to chuck it on the drive end and support the commutator end some way, a inch board with a proper sized hole drilled in it will work. Clamp it in a vise, oil the hole and it will work fine. On the later style Delco starters the bearing end plate can be used to do this by clampIng it in a vise. I have done this for years on starters and it works fine. Your field coils are likely your problem as others mentioned. You really need a Volt/ohm meter to check that there is continuity through them. This can be done with the battery, a jumper wire and a test light. Connect the jumper wire from one battery terminal to the brush lead. Then connect the test light lead to the opposite battery terminal. Then touch the light probe to the opposite end of the field lead at the contact switch. If the light lights it means there is continuity. (The contact switch needs to be removed for this) You should also touch the starter case with the test probe, if it lights there you have a short in the windings to the case. Removing the contact switch, brings up another point. Are you sure the contact switch ran by the rod is making proper contact? After a lot of use those contacts burn down and can be very fussy to get them to contact properly.

 

[Paul 300 U]

Hello. I have a 1961 Cub I bought it a few months ago. The starter didn't work, it came with hand crank! Fortunately it's pretty easy to start with the crank but I'd like to get the starter working properly. Today I removed the starter. All in all it looked pretty good I thought. I'm not 100% on what I'm looking at but it appears the brushes are in tact and making contact. The wires are all connected. The armature looks ok but I cleaned it up a bit. After I cleaned it and reassembled I bench tested using a 6 volt battery and jumper cables attached to the stud on the starter and to the starter housing and nothing happens. What steps can I take to try and repair? It's my first time through one of these. Thanks as always. Paul

Thanks for the replies. Bad news. I was planning on attempting some of these fixes but with snow coming tomorrow I decided to just put it back together so I would have it ready to at least crank start. I reassembled and attached to the tractor. As I was hooking up my battery cables I heard a brief electrical crackle and quickly unhooked the battery. Apparently I left the pull ON/OFF switch in the ON position so I thought maybe that was the problem. I reattached the battery (POSITIVE to ground) and now there is nothing. The Anmeter gauge doesn't move in either direction. Nothing happens when I flick the on of button. Where do I start to diagnose the problem. Thanks for the help in advance. Paul

 

[used red MN]

Thanks for the replies. Bad news. I was planning on attempting some of these fixes but with snow coming tomorrow I decided to just put it back together so I would have it ready to at least crank start. I reassembled and attached to the tractor. As I was hooking up my battery cables I heard a brief electrical crackle and quickly unhooked the battery. Apparently I left the pull ON/OFF switch in the ON position so I thought maybe that was the problem. I reattached the battery (POSITIVE to ground) and now there is nothing. The Anmeter gauge doesn't move in either direction. Nothing happens when I flick the on of button. Where do I start to diagnose the problem. Thanks for the help in advance. Paul

Did you only remove the starter during this operation, nothing else was messed with? I believe Cubs have the oval box with the light switch and ammeter in it. Open that up and look for a problem like a short out in there.

 

[Janicholson]

Thanks for the replies. Bad news. I was planning on attempting some of these fixes but with snow coming tomorrow I decided to just put it back together so I would have it ready to at least crank start. I reassembled and attached to the tractor. As I was hooking up my battery cables I heard a brief electrical crackle and quickly unhooked the battery. Apparently I left the pull ON/OFF switch in the ON position so I thought maybe that was the problem. I reattached the battery (POSITIVE to ground) and now there is nothing. The Anmeter gauge doesn't move in either direction. Nothing happens when I flick the on of button. Where do I start to diagnose the problem. Thanks for the help in advance. Paul

A test light is your friend. The test from battery post to post (not the terminal, the post itself) Then from one post to the opposite terminal if the light keeps lighting all is well. next from the other post to the other terminal Then from ground to negative terminal. Then from ground to to the starter switch, then the amp gauge, then the other side of the gauge, then the ignition switch input wire. At some point the light will fail to light, identifying your failed wire or connection. Jim source of light

 

[rustred]

Hello. I have a 1961 Cub I bought it a few months ago. The starter didn't work, it came with hand crank! Fortunately it's pretty easy to start with the crank but I'd like to get the starter working properly. Today I removed the starter. All in all it looked pretty good I thought. I'm not 100% on what I'm looking at but it appears the brushes are in tact and making contact. The wires are all connected. The armature looks ok but I cleaned it up a bit. After I cleaned it and reassembled I bench tested using a 6 volt battery and jumper cables attached to the stud on the starter and to the starter housing and nothing happens. What steps can I take to try and repair? It's my first time through one of these. Thanks as always. Paul

well nothing happened,... i would look into the solenoid on that starter. all i do is emery the commutator then clean out the segments and check the armature with an ohm meter. not everyone has a growler, not even me. when u have nothing happening its usually them soleniods as long as u have power going to it.

 

[Paul 300 U]

Did you only remove the starter during this operation, nothing else was messed with? I believe Cubs have the oval box with the light switch and ammeter in it. Open that up and look for a problem like a short out in there.

Thanks Used Red. My first thought was that I mis wired starter when I put it back together and that was what caused the short. Your reply made me think back to yesterday when I tucked the previous owners wiring under the hood of the tractor into the original wiring harness clamps. Most of his wiring, which appears was done to make the lights work was fairly tidy but there were a few wires left out of the zip tie bundles he made. A few looked sketchy but I didn't think to much about it. I pulled them out after your reply and were fried. I removed the bad and added new. My question is what else would have been damaged by this shorting out.
Thanks! Paul

 

[Paul 300 U]

A test light is your friend. The test from battery post to post (not the terminal, the post itself) Then from one post to the opposite terminal if the light keeps lighting all is well. next from the other post to the other terminal Then from ground to negative terminal. Then from ground to to the starter switch, then the amp gauge, then the other side of the gauge, then the ignition switch input wire. At some point the light will fail to light, identifying your failed wire or connection. Jim source of light

Hi Jim thank you for your illuminating reply!. I found out what caused the short. I explained it in my reply to Used Red MN. I fixed the bad wiring but need to reinstall the starter which I removed again after the short occurred. My question is what other problems would this have caused? Thanks Paul

 

[Paul 300 U]

Did you only remove the starter during this operation, nothing else was messed with? I believe Cubs have the oval box with the light switch and ammeter in it. Open that up and look for a problem like a short out in there.

I forgot to attach pictures!

 

[used red MN]

Thanks Used Red. My first thought was that I mis wired starter when I put it back together and that was what caused the short. Your reply made me think back to yesterday when I tucked the previous owners wiring under the hood of the tractor into the original wiring harness clamps. Most of his wiring, which appears was done to make the lights work was fairly tidy but there were a few wires left out of the zip tie bundles he made. A few looked sketchy but I didn't think to much about it. I pulled them out after your reply and were fried. I removed the bad and added new. My question is what else would have been damaged by this shorting out.
Thanks! Paul

As rustred replied nothing probably happened. It just shorted and burned one of the wires off must have been the wire to the Generator or the ignition feed(since you had the ignition on) Any wires to the lights should not be energized unless the lights are turned on. As long as you can start it by the crank, the lights work and the generator charges you will be set to push that snow.

 

[used red MN]

Hi Jim thank you for your illuminating reply!. I found out what caused the short. I explained it in my reply to Used Red MN. I fixed the bad wiring but need to reinstall the starter which I removed again after the short occurred. My question is what other problems would this have caused? Thanks Paul

You don’t have to put the starter back on. Just bolt the battery cable and the one wire together and tape it. Whether the starter hole is open or not will make no difference. If it sets out and snow is falling or blowing you probably want to jam a wad of newspaper in the hole so the snow doesn’t blow onto the warm clutch and melt, then freeze possibly causing some problem.

 

[Paul 300 U]

well nothing happened,... i would look into the solenoid on that starter. all i do is emery the commutator then clean out the segments and check the armature with an ohm meter. not everyone has a growler, not even me. when u have nothing happening its usually them soleniods as long as u have power going to it.

Rust Red. Thanks for the reply. I'm not sure if you are responding to my original problem with starter doing nothing or the second problem when the wires shorted and the nothing happens with the Anmeter etc. when trying to start with the starter reinstalled . Looks like your response works either way. Thanks Paul

 

[Paul 300 U]

You don’t have to put the starter back on. Just bolt the battery cable and the one wire together and tape it. Whether the starter hole is open or not will make no difference. If it sets out and snow is falling or blowing you probably want to jam a wad of newspaper in the hole so the snow doesn’t blow onto the warm clutch and melt, then freeze possibly causing some problem.

Used Red. Thanks for that information! I guess I' should have know that! Paul

 

[John M]

Hello. I have a 1961 Cub I bought it a few months ago. The starter didn't work, it came with hand crank! Fortunately it's pretty easy to start with the crank but I'd like to get the starter working properly. Today I removed the starter. All in all it looked pretty good I thought. I'm not 100% on what I'm looking at but it appears the brushes are in tact and making contact. The wires are all connected. The armature looks ok but I cleaned it up a bit. After I cleaned it and reassembled I bench tested using a 6 volt battery and jumper cables attached to the stud on the starter and to the starter housing and nothing happens. What steps can I take to try and repair? It's my first time through one of these. Thanks as always. Paul

By stud, do you mean the lug on the switch, or the stud the switch contacts?

 

[used red MN]

Rust Red. Thanks for the reply. I'm not sure if you are responding to my original problem with starter doing nothing or the second problem when the wires shorted and the nothing happens with the Anmeter etc. when trying to start with the starter reinstalled . Looks like your response works either way. Thanks Paul

Well I am not sure which question that is in response to. Per the forum “reply” layout it is after you reinstalled the starter. He is confused by mentioning a solenoid which your setup is not using. Now this is partly my fault that I am not as familiar with the pull rod style starters. The post by JohnM brings up a point I did mention it on the end of my first reply sort of as an afterthought. When you tested your starter after assembly did you have the contact switch installed? If so you would have to activate the start lever to test the starter operation which you don’t mention. Otherwise, ideally you had the switch off and were jumping right to the contact stud on the case in the picture. Sorting all these details out helps determine if the starter is still actually not responding or if the problem is in the contact switch operated by the pull rod.

 

[Paul 300 U]

First off very few people have the machinery to “undercut” an commutator of an armature. That means to groove out the insulation between the copper segments. This is not that critical on a starter. It is far more beneficial when the armature is being used in a generator. People are going to cringe, but I was shown this trick by an old mechanic. Place the armature in a drill press by clamping the shaft that sticks out past the commutator in the chuck. Run it on a slow speed and stroke a sharp file on the commutator. Be careful to stay away from the step-up on the segments that lead up to a bigger diameter to where the windings attach. Finish it with some 180 grit or finer emery tape. You can also do this with a hand drill but most only have a 1/2” chuck so you have to chuck it on the drive end and support the commutator end some way, a inch board with a proper sized hole drilled in it will work. Clamp it in a vise, oil the hole and it will work fine. On the later style Delco starters the bearing end plate can be used to do this by clampIng it in a vise. I have done this for years on starters and it works fine. Your field coils are likely your problem as others mentioned. You really need a Volt/ohm meter to check that there is continuity through them. This can be done with the battery, a jumper wire and a test light. Connect the jumper wire from one battery terminal to the brush lead. Then connect the test light lead to the opposite battery terminal. Then touch the light probe to the opposite end of the field lead at the contact switch. If the light lights it means there is continuity. (The contact switch needs to be removed for this) You should also touch the starter case with the test probe, if it lights there you have a short in the windings to the case. Removing the contact switch, brings up another point. Are you sure the contact switch ran by the rod is making proper contact? After a lot of use those contacts burn down and can be very fussy to get them to contact properly.

Used Red MN thanks for the detailed step by step instruction. Since I don't know a lot about this it allows me to at least connect what I know to towards fixing the problem. Paul