Which farmall C ? ignition problems

ray1377

New User
I don't really know where to begin. I'm not a tractor mechanic by no means. I'm trying to help my father-in-law get his old Farmall C going. I say Farmall C with a big of doubt. And I realize if I had the serial number off it that would give any of you more information. I'm at work now and can't get the serial number until this weekend. I thought if I explained the issue it might jog someone's brain. I'm going to post some pictures If I can figure out how. I have spent hours on the internet searching for an image that matches what is on his tractor but haven't had any luck. To describe it, his distributor cap is rectangle, not round. It only has 4 spark plug wire terminal points on it, no center coil terminal. The spark plugs get their fire from the coil but it travels internally through a small channel up the side of the coil across the top and ends at the button that pushes onto the rotor. His coil isn't externally mounted like a vehicle coil, nor is it square with the discharge terminal coming out of the top side pointing sideways. His coil is underneath a square / rectangle cover and when you take the cover off, there is a thick wire covered in insulation that looks sort of like a top mounted side terminal coil but this thick wire goes through the distributor housing and touches the copper tab on the inside edge of the cap. His rotor plate has a copper ring all the way around it. He can't get it to fire and has taken the whole dang thing apart to "clean" it. I've read that if any of this system get's grounded to metal it won't fire. Can someone shed a little light on this? It sure would make one old gentleman very happy.

Thanks
which-distributor-.jpg
coil-drawing.jpg
 
You have a magneto, but not the IH magneto these tractors usually had. No doubt somebody had magneto trouble and solved it by installing whatever magneto he had available. This isn't necessarily a problem but may complicate finding tune-up parts. Look it over for a company name. Post a picture here and somebody may recognize it. Do an internet image search for "tractor magneto" and you may find a matching unit that is identified.
 
I don't really know where to begin. I'm not a tractor mechanic by no means. I'm trying to help my father-in-law get his old Farmall C going. I say Farmall C with a big of doubt. And I realize if I had the serial number off it that would give any of you more information. I'm at work now and can't get the serial number until this weekend. I thought if I explained the issue it might jog someone's brain. I'm going to post some pictures If I can figure out how. I have spent hours on the internet searching for an image that matches what is on his tractor but haven't had any luck. To describe it, his distributor cap is rectangle, not round. It only has 4 spark plug wire terminal points on it, no center coil terminal. The spark plugs get their fire from the coil but it travels internally through a small channel up the side of the coil across the top and ends at the button that pushes onto the rotor. His coil isn't externally mounted like a vehicle coil, nor is it square with the discharge terminal coming out of the top side pointing sideways. His coil is underneath a square / rectangle cover and when you take the cover off, there is a thick wire covered in insulation that looks sort of like a top mounted side terminal coil but this thick wire goes through the distributor housing and touches the copper tab on the inside edge of the cap. His rotor plate has a copper ring all the way around it. He can't get it to fire and has taken the whole dang thing apart to "clean" it. I've read that if any of this system get's grounded to metal it won't fire. Can someone shed a little light on this? It sure would make one old gentleman very happy.

Thanks
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Someone stuck an aftermarket magneto on it. Should be fine,if you can identify it, find parts and work on it. Another, simple solution is to purchase a distributor and swap it. I have a couple different distributors that will work. And I'm happy to help you make the swap. Very simple to do. Parts are cheaper and more readily available for a distributor. We ship parts nearly every day. Bottom distributor is a Delco,common aftermarket upgrade from a magneto. The top one is the IH distributor that replaced the magneto. Both are for sale........or call / text me. Happy to help with the magneto, might be a simple fix!
 

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Someone stuck an aftermarket magneto on it. Should be fine,if you can identify it, find parts and work on it. Another, simple solution is to purchase a distributor and swap it. I have a couple different distributors that will work. And I'm happy to help you make the swap. Very simple to do. Parts are cheaper and more readily available for a distributor. We ship parts nearly every day. Bottom distributor is a Delco,common aftermarket upgrade from a magneto. The top one is the IH distributor that replaced the magneto. Both are for sale........or call / text me. Happy to help with the magneto, might be a simple fix!
Thank you sir, I appreciate the heads up on conversion parts. At this time my father-in-law would really like to try and get it going with what he has on hand. I guess I'm more or less asking for information on "magneto's" and their pitfalls. I'm thinking as old as it is and the condition of the wiring I'm thinking he has a grounding issue causing no spark. But like I stated in the original post, I'm no tractor mechanic. I've worked on cars, trucks, motorcycles, boats and four wheelers so I'm not completely blind here. Thanks for the info so far fellows. I'll try to get some pictures of his ignition parts posted this weekend.

Thanks
 
@ray1377
I guess I'm more or less asking for information on "magneto's" and their pitfalls. I'm thinking as old as it is and the condition of the wiring I'm thinking he has a grounding issue causing no spark.

Magnetos work fine on old tractors. They sometimes need parts and can have internal grounding problems, but that is not the first and most probable place for the problem. First figure out what mag it is. There are a gazilion mag troubleshooting guides/advice on this site and the internet. Read enough to be able to unpack the advice you are given. A lot of it will be more complex than you need and be harder to understand untill you get your head around it. Some brands the parts are harder to find and more expensive. Cleaning connections and setting points and timing correctly often is all it needs.
 
Thank you sir, I appreciate the heads up on conversion parts. At this time my father-in-law would really like to try and get it going with what he has on hand. I guess I'm more or less asking for information on "magneto's" and their pitfalls. I'm thinking as old as it is and the condition of the wiring I'm thinking he has a grounding issue causing no spark. But like I stated in the original post, I'm no tractor mechanic. I've worked on cars, trucks, motorcycles, boats and four wheelers so I'm not completely blind here. Thanks for the info so far fellows. I'll try to get some pictures of his ignition parts posted this weekend.

Thanks
Clean the points in the magneto, maybe the only issue.......but I highly recommend " Teddy52food".....he is a guru / genius when it comes to magneto issues!
 
Clean the points in the magneto, maybe the only issue.......but I highly recommend " Teddy52food".....he is a guru / genius when it comes to magneto issues!
Hi grand pa I was wondering what happened to you as I have not seen you on much. Hope all is well
 
I don't really know where to begin. I'm not a tractor mechanic by no means. I'm trying to help my father-in-law get his old Farmall C going. I say Farmall C with a big of doubt. And I realize if I had the serial number off it that would give any of you more information. I'm at work now and can't get the serial number until this weekend. I thought if I explained the issue it might jog someone's brain. I'm going to post some pictures If I can figure out how. I have spent hours on the internet searching for an image that matches what is on his tractor but haven't had any luck. To describe it, his distributor cap is rectangle, not round. It only has 4 spark plug wire terminal points on it, no center coil terminal. The spark plugs get their fire from the coil but it travels internally through a small channel up the side of the coil across the top and ends at the button that pushes onto the rotor. His coil isn't externally mounted like a vehicle coil, nor is it square with the discharge terminal coming out of the top side pointing sideways. His coil is underneath a square / rectangle cover and when you take the cover off, there is a thick wire covered in insulation that looks sort of like a top mounted side terminal coil but this thick wire goes through the distributor housing and touches the copper tab on the inside edge of the cap. His rotor plate has a copper ring all the way around it. He can't get it to fire and has taken the whole dang thing apart to "clean" it. I've read that if any of this system get's grounded to metal it won't fire. Can someone shed a little light on this? It sure would make one old gentleman very happy.

Thanks
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Interesting mag design. Welcome to YT.
As you turn the engine there should be 2 clearly audible clicks coming from the mag every revolution. if no clicks, the Impulse coulping is not working, and that will keep it from making spark at cranking speeds. Look up Impuls coulpings for Magnetos. Jim
 
Stay with the magneto . robust ignition for farm applications . The magneto is compact robust ignition and will start the tractor with out storage battery . This you will find will far out way a distributor that depend a fully charge storage ,or a source for power.
 
Update: I have posted pictures of his tractor ignition set up. Any advise will be greatly appreciated.

Thanks
 

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No sir, the coil cover is not missing. Just removed so he could to the coil. And yes I did get a picture of the coil tag. Its a splitdorf. Now if I could just find some information on how it's suppose to function and what might be causing the tractor to have NO SPARK.
Thanks
 

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No sir, the coil cover is not missing. Just removed so he could to the coil. And yes I did get a picture of the coil tag. Its a splitdorf. Now if I could just find some information on how it's suppose to function and what might be causing the tractor to have NO SPARK.
Thanks
Not really familiar with this brand, but it looks to me like the points are missing. Or at least the part that has the cam follower.
 
No sir, the coil cover is not missing. Just removed so he could to the coil. And yes I did get a picture of the coil tag. Its a splitdorf. Now if I could just find some information on how it's suppose to function and what might be causing the tractor to have NO SPARK.
Thanks
Dunno what you mean by the "coil tag", I was referring to the tag on the mag body that is clearly shown in the photo I posted.

"if I could just find some information on how it's suppose to function and what might be causing the tractor to have NO SPARK"

One of the links I posted was to the Service Manual, I'm NOT sure what more info you are wanting to find?

That being said, if the mag was working in the fairly recent past, the most likely reason for no spark would be dirty/corroded/worn breaker points that are not making good contact, followed by a failed condenser.
 
The points are not installed in these pictures. They are in a box beside the tractor waiting for my father-in-law to put them back on.
The "coil tag" is what I called the identification tag on the side of the magneto assembly below the coil cover.
Thanks
 

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