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

 

[David-Davies]

Yes you can jump from your hot wire, or the battery, and touch each wire, to see what happens. You will atvate the starter, but it proabaly won't start, unless you jump the wire for the injector pump. Then again as said you have safty switches, witch may not let any thing work, so make sure that you engage, all switches. Do you have bright head lights, or are they a little dim?? Do they go dim when you try to activate the starter??
Dave

 

[Jason_MI]

David; I get no lights at all.

Edited to add> Okay; just spent several hours out there in the cold garage. I'm pretty sure it's not the safety switches; I bypassed all of them and still get nothing. This afternoon, I'll try to hotwire it from where the switch is; my plan is to simply jumper from the hot to each of the accessory wires. Does that sound reasonable?

Also, when I first hooked up the hot to the switch this morning, there was a spark...does that indicate anything like a ground situation that shouldn't exist?

Just kind of grasping at straws at the moment; I mean, there are SO many wires and harnesses on this dumb thing.

 

[Soundguy]

i think i'd check wire to the solenoid first and see what it hits.. via the schematic. check safety switches in that line.. might be a trans neutral interlock.. etc..

soundguy

 

[David-Davies]

Hello Jason MI. Did you try using a set of jumper cables from the battery. Ground on the battery to a bolt or good ground on the starter. touch the hot clamp to the starter. Not the solenoid, were the battery is bolted, on, but the outher bolt on the solenoid, that has a metal tab that goes in to the starter. Their should be a large spark, and the starter should turn over, but may not engage the starter. If you don't have a large spark, when you touch the starter, touch the hot clamp to a good ground. Their should be a large spark. Then touch the hot clamp to the ground clamp. You should have the same spark at all three spots, with maybe a little less at the starter. IF NOT you have a bad battery ground, dirty battery post, bad battery. If you get a large spark, then, test each circuit, one at a time. Disconect all outher wires, except the ones for the circuit that your testing. This is importent test, You must make sure that you eliminate, all battery problems before testing any circuits, or you`ll just go around in circles
Dave

 

[David-Davies]

PS. If you touched the hot tab on the key, and nothing was hooked up, and you got a spark, your key has a short. Test with an ohm meter, from each tab to the side of the swith, there should be no curent flow from the tabes to the side of the swith. Of course touching each tab with a hot wire is quicker. Their should be no spark.
Dave

 

[Jason_MI]

Thanks; I'll try those tonight.

 

[Jason_MI]

First off, let me say that I owe a huge, huge, huge thanks to those that have responded. Mr. Davies jogged a memory I had from long ago, which I followed. At the time, I had a relatively young riding lawn mower that failed. I tried everything to get it going, but nothing worked. My neighbor---rest his soul---said that the first thing you do is clean the terminals on the battery and the battery leads. I thought he was nuts, as they looked fine, but after some sandpaper; funny; it worked.

The same thing happened here. I took off the battery connections, and spent a GOOD deal of tiem cleaning them, sandpapering them, and making them basically bright. I took apart the connectors and soaked them in baking soda and water, used sandpaper on the wires, sandpapered the terminals on the battery.

I took a good long time, and as soon as I was done; well....the thing works. So once again, the simplest solution is the best one.

Thanks again, Mr Davies. I owe you on this one.

 

[David-Davies]

Glad to of helped. But David-Davies is my first name, I'm Welsh.
Dave

 

[Scrambler82]

Did you use some terminal paste on the battery terminals ?
It help with corrosion.