Mower Blowing Fuses

[jbell1981]

I am getting conflicting info so running it past you guys to see what you think.

As stated in another post, I picked up a 1988 Toro Groundsmaster 117 at an auction. It seems to run fine with out any issues when the PTO is not engaged. When the PTO is engaged it will run fine for about 20 minutes and then blow the 30 amp fuse. If I put in a new fuse it will blow them continuously until I let it cool down for a couple hours. If I let it cool I can run it for another 20 minutes before the fuse blows.

The local Toro dealer told me that the clutch is bad and if I replace it that should solve the issue.

Another party said it is most likely a wiring issue somewhere(ie, bad ground, bad connection/switch, bare wire). After a brief look I didn't notice anything glaring other than it looks like it was re-wired to bypass the safety switch in the seat (if you get off the seat with the pto engaged it should kill the engine).

Maybe someone with more experience can correct me if I am wrong, but if it was a wiring issue wouldn't it blow the fuse immediately after engaging the pto? It doesn't make sense to me that this would cause it to blow only when the mower is "hot".

The clutch is nearly $400 if I buy it from Toro although I have been able to find them online in the $250 range. I would rather not spend that if there may be another solution.

Any thoughts?

On a side note, anyone know the value of these mowers in running/mowing condition? I can't seems to find many for sale on line to get a grip on what they go for. I paid 600 at the auction. Besides this issue it needs new blades and some brake work. If thier value is is high enough I wouldn't have as much of an issue with the cost of the clutch. I don't plan on selling it but I don't want to sink money into a pit either.

[delcecchi]

Silly question, but is the clutch electrically operated? Is there a connection from the clutch to the electrical system?

[jbell1981]

Yes, it is an electric clutch.

[Tom7227]

After seeing it I wonder whether that part is unique to the mower you own. I had a simplicity mower and had to pull that part and it sure looks a lot like yours. If you could find some sort of cross reference chart maybe you would have more luck finding a replacement. Try going to Jacks Small Engine HSOforum and see if you can figure it out there, or maybe even call them. I have found them to be ver.y helpful

[delcecchi]

Then it could be causing a problem when it heats up. Is that a toro part number sticker on it? Or some other company?

[jbell1981]

That's just a pic I found online of the part. That particular one looks to be made by Ogura.

[Tom7227]

Shooting in the dark but wouldn't there have to be a solenoid in the system so that when you activated the mower the solenoid would click on and push something to engage the clutch? After you have run it and it quits working can you hear the solenoid click when you activate the mower - with the motor off? If not then maybe there is something wrong with the solenoid so that when it gets warm it malfunctions and gets stuck causing the fuse to blow.

Another option might be that something in the drive system locks up when it gets hot and puts too much strain on the clutch.

I don't like either of these ideas all that much but you don't seem to be getting a lot of input on this question.

[jbell1981]

There is a starter solenoid but not one specific to the clutch if that is what you mean. I've attached a wiring diagram so you have an idea of what's all there.

The solenoid is rather cheap so maybe I should just replace it and see if it helps.

I am going to remove all of the sheet metal covers this weekend on go through all of the wires thoroughly, clean all of the connections and grounds and look for any bare wires that could be shorting. If that doesn't solve it then I'll probably get the clutch.

[JOHNBIGDOG]

I had a very similar problem on my john Deere 314. Garden tractor. The pto clutch, very much similar to yours went bad. My tractor has one circuit breaker for the whole electrical system which made it hard to diagnose. Eventually you could smell a burning electrical smell and then the mower would shut down. Over a few weeks of this I burnt up the ignition switch and wire harness, due to the bad clutch. I replaced the clutch, wire harness, ignition switch and have been happily mowing for a while.

If you want to be 100% certain ohm out the clutch cold, then ohm out the clutch hot. Cold it should have a high resistance reading. Hot (if its bad) would have a low resistance reading. Also you should never have any continuity to frame ground with the clutch circuit.

[Jeremy airjer W]

I would agree with ohm checking when hot. If there is very little resistance compared to when it is cold than the clutch is the issue.

Unplug the clutch connector before checking.

[Trashguy]

Kept blowing fuses on my Groundmaster 120 a few years ago. Replaced the deck clutch (mower) and it took care of my problem. Bought the clutch off hsolist for like $260 or so. Find out what your part number is and you should be good to go searching hsolist.

[jbell1981]

I went through some of the wires near the clutch the other day. I replaced some wire that seemed to be smaller gauge than the rest but this has had no affect on the problem.

When I was cutting the wires to splice new connections I noticed that the wires coming out of the clutch to the first connection were discolored and almost black. I cleaned the areas where I was connecting them. Is this a sign of a bad clutch/connection or just normal discoloration for 24 year old wire?