Ignition switch, or something else?

[Jason_MI]

I've had minor switch issues (I assume switch), in the past where, as on most diesel tractors, you turn the key to the left to warm up the glow plugs, and a little light goes on, then you turn it right to engage the starter. Sometimes it seems to simply not work until I wiggle it. Last week, when we had a lot of snow, I had no trouble getting the tractor started, and plowed on my merry way for a good four hours. I parked it in the garage, shut it off, and that was it. When I tried to start it again, I got nothing. Left/right; no kick, and no lights.

So I began taking the dashboard apart, and got the switch out. Once while I was messing with it (in removing it), it briefly worked again--that is, turning the key to the left, I got the glowplug light. To the switch, there are five wires; a ground, hot, and three accessory. TO the switch, I have full power (same as at the battery), and a good ground. I think that shows that it's not grounding out somewhere, as one of those wouldn't be correct (I think). I can trace the accessory wire that goes from the switch to the glowplug indicator.

My first guess (hope), is that the switch is messed up. I picked up a cheap automotive one, and that still doesn't do the trick (I'm wondering, however, if it's not wired slightly differently; turning it to the left might not do what turning the tractor one to the left).

My second thought was that it could be that wiring harness; but given that I have continuity in the glow plug light wire, and both power and ground, I htink at least the glowplug would light if the switch was good.

My last thought is that it might be grounding or shorting somewhere else, but wow; there are a LOT of wires and wiring harnesses on this tractor. Almost like a car.

Thoughts?

Thanks, as always.

Oh; this is a Cub Cadet (Misubishi) 7235

 

[Scotty370]

I'm not and expert by any means, but I'm thinking that the current continuity (IE indicator light) that your seeing, is only an indication that your getting current to a solinoid somewhere thats going to 'trip' to send some 'serious' amperage to the glow plugs! Guess what I'm trying to say, is you need a schematic. May not be the switch, but the solinoid. You may have some grounding problems.........~Scotty

 

[David-Davies]

Hello Jason MI. When you fix electrical problems, you must first make sure that you have not only voltage, but curent flow.If you turn the key and have nothing, I would first test the battery, for a short, positve, and groung for contact. [clean the post] Disconect the ground wire from the battery and jump it with a good battery [put the ground jumper to a good groung not the battery cable]. That will tell you if you have a battery problem. Secondly use a jumper wire to by pass the switch, when the key doesn't work. If it workes with the jumper, and not the key, it's your switch. If it doesen't work with the jumper, then your problem is else were. Your glow plug light may be lose or not working. The fact that your starter doesn't turn over, implys that you have a common problem. Witch brings me back to battery, or the switch, and I'd would be looking for a bad ground

David-Daves

 

[Jason_MI]

Thank you both for your help; I'll try those out tonight and see what happens.

 

[Soundguy]

try jumpering fromt he back of the old switch to the individual contacts and see what you get.

soundguy

 

[banjodunn]

G'day as soundguy said try jumping across the back of the switch, most automtive switches are different to ag but there are plenty of aftermarket ag switches available with a preheat position. Hope you get it worked out


Jon

 

[jerrywane]

dont know if this will help,but this site has alot of mauals on it http://www.tradebit.com/filedetail.php/3184115-cub-cadet-mitsubishi-compact-tractor-service-repair this link will take you there

 

[racerboy832]

I just went through this the other day. Mine had Batt voltage to one. Key Left Batt Voltage to Glow plugs. Key on, Voltage to lights, Key start, Voltage to starter solenoid and Glow Plugs. I was losing too much current to the glow plugs on the Start position so it cranked slow. There was a jumper wire so disconnected it and I made it glow plugs only on start position and it cranks fast now. Check your safety switches too. Power from the start on mine, goes through the safety switches then to the starter. Check Yanmar Ignition switch on ebay. They had exact copies of mine for the Massey 1020 Diesel.

 

[Jason_MI]

Thanks.

I'm getting great voltage up to the ignition switch, and have tried bypassing the battery and jumping it; nothing. Fuses are good. Fusible links have continuity. How do I hotwire this thing? I have all five wires bare right now. Can I simply make a connection between hot and the wire going to the starter/solenoid, just to see if it turns over?

 

[jerrywane]

Just thinking ,not there .....but did you check saftey sw/clutch/P.T.O......just thinking