Ignition Switch Repair or Replace

[alfreema]

I went out and mapped the wiring on my cub and it has nearly been reduced to the bare minimum. The ignition switch has been bypassed, the entire light circuit has been removed, etc. So I want to take it one step at a time and I am going to go remove the ignition switch and thoroughly clean it and hope to repair it (if broken). It appears to be original and I hate the thought of removing anything original, especially if there is even a cusp of a hope of repairing and restoring it.

1) It's just kind of dangling in the hole in the console. How do you remove it? (It may be super obvious when I am out there, but it's really cold at it's location and I am not sure what tools to take).

2) Assuming it has been bypassed because it was "bad", is repairing and restoring it usually feasible?

Thanks!

[AL Farmall Boy]

I've not seen many original switches at all that go bad. Does it look like either of the switches below? If not, then it isn't original. It's probably best to just take all wiring off the tractor and start over. I've done them before and they're super easy to wire. Pictures would help us and the year of your tractor (serial number) would also because the later ones had 2 styles of a key switch. Look closely at yours and see if it matches any of those below. It is also possible that it could be one like the older style (2nd switch pictured) with just 1 terminal instead of 2 terminals. Those were for magneto equipped tractors and the ones with 2 terminals were for Distributor equipped tractors.

* Photos courtesy of TM Tractor Parts (http://www.tmtractor.com)

Cub Ign Switch (pushbutton).JPG (73.63 KiB) Viewed 3315 times

Cub Ign Switch (Old Style Distributor).JPG (92.13 KiB) Viewed 3315 times

The attachment Cub Ign Switch (key start).JPG is no longer available

[torchred89]

I would just replace it for $11.80 http://www.tmtractor.com/new/el/1215fp.htm

[alfreema]

I've not seen many original switches at all that go bad. Does it look like either of the switches below? .... Pictures would help us and the year of your tractor (serial number) would also because the later ones had 2 styles of a key switch.

Oops, sorry for leaving out the important piece of info: The cub is a '48 still 6 volt with magneto. It's this style switch:

Cub Ign Switch (Old Style Distributor).JPG

It's probably best to just take all wiring off the tractor and start over. I've done them before and they're super easy to wire. It is also possible that it could be one like the older style (2nd switch pictured) with just 1 terminal instead of 2 terminals. Those were for magneto equipped tractors and the ones with 2 terminals were for Distributor equipped tractors.

Yes, that's my exact plan, to replace every bit of the wiring. And since half of it has been bypassed I was planning on readding the missing components one at a time, so if they cause a problem it will be easy to isolate (e.g. worked before I added these two wires, now it doesn't).

That picture is super helpful. Now I know how to get it out!

[alfreema]

I would just replace it for $11.80 http://www.tmtractor.com/new/el/1215fp.htm

Yes, if it's beyond repair I will do just that. But I got a feeling I am going to be order quite a few replacement components so I want to repair everything I can to help keep the cost down and keep it as bone stock as possible. It's missing it's headlights and rear light, the voltage regulator is "wrong" (only has 3 terminals), etc.

[Bob McCarty]

If you still have the magneto, you will find only one prong on the back. I remember Bigdog fixed one years ago by carefully opening up the crimp on the back end and cleaning up the corrosion inside. I don't remember how he resealed it though.

Bob

[ScottyD'sdad]

One of our members has repaired the switches. He grinds off the tabs, holding the rear cover on, cleans the contacts, and sticks the rear cover on, with a couple of dabs of epoxy glue. (He did mag type.)
Ed

[Like-em-all]

1) It's just kind of dangling in the hole in the console.

The ignition switch controls the magneto by grounding the circuit (to stop) or opening the circuit (to run). If the switch is not well attached to the console/chassis, then it will not operate as intended. Try installing the switch into the console hole by tightening the attaching nut, if one exists, or adding a replacement retaining nut if it is missing.

Bill

[alfreema]

If you still have the magneto, you will find only one prong on the back.

I just drove over and pulled it off. It's got one prong just like you said.

Here's some questions ...

1) If you try to start a cub (6 volt magneto setup) with the ignition switch off, will it actually crank a little but very slowly or will it be completely dead and not even crank? I know that is a dumb question but I have to ask it. It seems to me it should be completely dead due to an open circuit, but maybe my assumption is wrong? The reason I ask is that the wire leading to the switch has been disconnected the entire time I have owned it but it still starts (but only after a million attempts). The wire does lead to the magneto, but it's not connected to the back end of the starter (or anything else).

2) Which leads me to this question. At the end of the wire leading from the magneto is the "back end" of the ignition switch. The wire is screwed to the prong, and prong is attached to a "plate". The "plate" has a dual prong "clip" that it looks like the plunger of the switch should slide into to make contact. But there is nothing to hold the "plate" to the main body. Does anybody have a picture of what holds that plate to the main body?

Hmmm. I think my hint is in this post "One of our members has repaired the switches. He grinds off the tabs, holding the rear cover on, cleans the contacts, and sticks the rear cover on, with a couple of dabs of epoxy glue. (He did mag type.)" It sounds like the tabs have been ground off already.

[alfreema]

1) It's just kind of dangling in the hole in the console.

The ignition switch controls the magneto by grounding the circuit (to stop) or opening the circuit (to run). If the switch is not well attached to the console/chassis, then it will not operate as intended. Try installing the switch into the console hole by tightening the attaching nut, if one exists, or adding a replacement retaining nut if it is missing.

Bill

It appears to be all here, minus the tabs to hold the back of the ignition switch on. But the wire hasn't been connected in a long time, so I am going to completely clean up this ignition switch, reinstall it, and then run a nice new wire.

[John *.?-!.* cub owner]

Using an ohm meter, when turned off (pushed in) the single post should ground to the case of the switch. When knob pulled out (run), no connection between terminal and case. Of course, that is assuming you are using the straight magneto, and not one that has been converted by using an external coil.

[alfreema]

Using an ohm meter, when turned off (pushed in) the single post should ground to the case of the switch. When knob pulled out (run), no connection between terminal and case. Of course, that is assuming you are using the straight magneto, and not one that has been converted by using an external coil.

Excellent. The magneto looks an original red one but it's so nice and shiny that I am guessing that a former owner either replaced it with a rebuilt original or some OEM replacement. Or maybe they just cleaned it up and repainted it one point. Once I clean the switch up I will do the ohm test.

One more question .. should the "knob" (the part you actually grab ahold of) be red? It's currently gray, and sorta looks like it was painted gray. But I think I have seen pictures where that part is red originally?

[John *.?-!.* cub owner]

They were naturally a gray color. I think they were originally painted, since everything else was, but do not paint the shaft.

[Scrivet]

...... to help keep the cost down ............ the voltage regulator is "wrong" (only has 3 terminals)

I wouldn't pitch it just yet. Are you sure it's a voltage regulator or could it be a cutout? If you still have a light switch how many positions does it have 3 or 4? If you're sure it's a regulator are you sure there's not a terminal on the bottom? It may be tough to see, might want to dismount the regulator, you need to clean up the grounds anyway

[alfreema]

...... to help keep the cost down ............ the voltage regulator is "wrong" (only has 3 terminals)

I wouldn't pitch it just yet. Are you sure it's a voltage regulator or could it be a cutout? If you still have a light switch how many positions does it have 3 or 4? If you're sure it's a regulator are you sure there's not a terminal on the bottom? It may be tough to see, might want to dismount the regulator, you need to clean up the grounds anyway

Haha, no I am not sure of anything! It's definitely some shiny new aftermarket part and it's bolted on a bracket hanging just in front of the magneto. One wire comes in from the ammeter and is connected to a terminal labeled battery. The other two terminals run up to the generator. This is either a voltage regulator and I do not have a cutout that I can see, or this is a cutout and I do not have a regulator that I can see. Based on a schematic I saw, I assumed this was the voltage regulator, as that is what the ammeter line runs to in the schematic (and connects to BAT).

By the way, I have seen lots of references to a "cut out" but I have no clue what the function of a "cut out" is?

Thoughts?