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Discussion Starter #1
Just got this tractor that has wiring problems. Some previous owner royally screwed up the wiring as I had cut, crossed, twisted back together wires, etc.. It has an electric pto switch (which is missing so not hooked up) but, correct me if I'm wrong, I don't THINK that will cause problems just for trying to start and stop the engine. Anyway, right now when I turn the key switch to "on", the red wire that goes from the battery pole of the solenoid to the key switch becomes warm. I think there should be a fuse there but it looks to have been cut out. When I try to start it, the solenoid clicks and the starter turns the motor over a little bit, but the battery doesn't have enough power. So I think the solenoid is good. So, right now my big question is why is that wire getting hot.. (it smokes and starts melting when a jump starter is on the battery too)

If I can fix the wiring, it'd be a great machine.. Its got the 6 speed hi-lo transaxle and 18hp Kohler M18 Horizontal.
 

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If it spent anytime stored outside, I'd pull the starter and take it apart and clean the contacts and check the brushes.

I have the same tractor and the same engine. Ive had the same problem as your describing. It was a bad starter both times it happened to me.

If needed, you can buy a starter rebuild kit for less then 15 bucks. I just did mine a few weeks ago, and it's working great.
 

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Discussion Starter #3
I don't think it could be the starter.. I've disconnected it from the solenoid for now while sorting out the wiring and I'm still having this problem.
 

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The alternator it is then it seems. I disconnected the alternator, turned the key switch to on, and after a good long while the wires still weren't getting warm. Makes sense as the guy I bought it from said the headlights didn't work..

Anyway, nice to know what the problem is although getting to the alternator looks like it will be a BEAR on this engine.. I've done some vertical shaft motors and they aren't too bad but this is my first horizontal engine. At a glance it looks like I might need to remove the engine? Because the flywheel is facing inward and it'd be impossible to get a puller in there to get it off.
 

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IF you posted the Sears 917.xxxxxx number, one could look at the correct schematic and see what you have.

Not an expert at this, but I thought GT 6000's had a vertical engine????

Typically the starting circuit goes through the PTO switch, so that you can't start the engine with the mower engaged.

Without being able to see the proper schematic, one doesn't know if you have Operator Presence Relay(s) that could be bad and drawing some amount of current, but not enough to instantly melt wires or other potential problem spots etc. etc.
 

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Discussion Starter #8
Tractor model: Craftsman 917.255960
Engine model: Kohler M18qs

Without the alternator or pto switch hooked up, I can still turn over the engine. Can't start but that is an unrelated issue (flooded, battery not charged enough)

Here's a picture:

 

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The alternator might be okay, it might be the regulator…the wiring diagram would be a huge help here.
 

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You want to know how the wires are currently hooked up? Oh boy that could be a tall order lol.. I'll see what I can do
 

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Yeah, that could be a nightmare. I was thinking of the original diagram. I'm thinking that the battery could be backfeeding the alternator windings through a bad diode or regulator, depending on your setup. I'm assuming the you have the alternator under the flywheel.
 

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Discussion Starter #12
I posted the tractor model number along with that picture if you know how to find the wiring diagram that way. But I'll get out there with my video camera and show you guys around it too. I also assume the alternator is under the flywheel. What is the regulator?
 

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I'm not sure whether you have a regulator or not, but a regulator takes the Alternating Current from the alternator, and rectifies it to the Direct Current that the battery needs. It also limits the voltage to the proper level, somewhere around 13.5 volts DC. It has diodes in it that can short, allowing current to flow uncontrolled, which could be heating up your wiring.
The regulator, if you have one, is typically a unit that's about 1½" square, about ½" thick, mounted to the blower housing. It will have 3 or 4 wires going to it - two to the alternator, one to the battery, and maybe one for ground.
Someone more familiar will come along and correct me if I wrong - I'm just relating my experience.
 

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Hi Puncher, I just finished up an artical in the Teck Exchange that may help you. I used an 18hp B/S opposed side fhadt engine simular to yours.

As a note, The wire from the key switch to the Wire from the Battery side should have a 30A Fuse. If you have the single wire alternator, then there should be a "dual diode" assemble close to the Key switch. A shorted diode will cause the wire to get hot, expecially if there is no fuse.

http://www.mytractorforum.com/showthread.php?t=218342
 

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Discussion Starter #16
There was no fuse when I got it; I did find a lose wire cut out just sitting there that had a blown 7.5 amp fuse though lol. So there is no fuse in it now but it is not getting hot without the alternator plugged in. "single" wire alternator? Two wires come out; ground and hot. Which splits into three; ground, hot to the headlight switch, and hot to the keyswitch. Is the duel diode thing you mentioned the regulator?
 

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The "box thing" you refer to is a relay, probably the "operator presence relay" that kills the engine under certain safety circumstances.

If those two wires are coming from the alternator, I don't think you have a regulator, just a diode in the wiring. That diode may be shorted, causing your hot wiring. Do you have an ohmmeter? You could check the diode/wiring for shorts if you do, without letting any more smoke out of the wiring.

ETA: with the way the PO cobbled the wiring, he may have eliminated the diode I mentioned.
 

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There was no fuse when I got it; I did find a lose wire cut out just sitting there that had a blown 7.5 amp fuse though lol. So there is no fuse in it now but it is not getting hot without the alternator plugged in. "single" wire alternator? Two wires come out; ground and hot. Which splits into three; ground, hot to the headlight switch, and hot to the keyswitch. Is the duel diode thing you mentioned the regulator?
The 2 YELLOW wires in are the AC from the alternator.
The other wire should be the 12V DC output from the regulator (RED)
An ORANGE wire splits off from the RED to the headlight switch.
 

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Looks like Bill has you "wired" now.:fing32: Yours has the Regulator and dual wire alt. Mine used the dual Diode and single wire Alt, Not interchangable, although I think a 15A Bridge recitifer could replace the regulatior as a low cost option. I personally have not tried this, but on paper it looks like it would work.
 
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