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ArTurf
07-09-2010, 07:29 PM
I have a '08 Super Z 25/54 and the pto will not engage. I have checked and power-12 volts is getting to the pto, yet it makes no effort to engage.

mowerconsultant
07-12-2010, 11:04 AM
Where are you getting the voltage reading from? the 2 prong plug that plugs into the clutch? if so then it sounds like your clutch winding is shot, you would need to replace the clutch.

Pj

ArTurf
07-12-2010, 11:16 AM
The voltage reading is at the connector on the pto. The mower has only 450 hrs and the clutch has been treated well, engaging & disengaging at the lowest possible rpm's. Didn't think it would be worn out so quickly compared to other commercial mowers I have had in the past.

ssgnai
07-12-2010, 11:52 AM
I had a short from worn off insulation on the line that runs from the back of the engine up to the harness under the seat. Wrapped it in tape, problem solved. You might check that too.

Steve

ArTurf
07-12-2010, 05:36 PM
The voltage reading is at the plug in on the clutch. Can I test the clutch itself with an ohm reading? or what? Is the clutch grounded anywhere?

mowerconsultant
07-14-2010, 02:13 PM
The voltage reading is at the plug in on the clutch. Can I test the clutch itself with an ohm reading? or what? Is the clutch grounded anywhere?

You can check the resistance and get the reading with testing it in the ohm's setting.

Pj

ArTurf
07-14-2010, 03:27 PM
I took an ohm reading on the clutch itself and it read 2.5-2.6 Good/Bad?

okievarmint
07-15-2010, 09:03 AM
The voltage reading is at the plug in on the clutch. Can I test the clutch itself with an ohm reading? or what? Is the clutch grounded anywhere?
The clutch pigtail supplies both power and ground. If you are getting voltage at one terminal, check for ground at the other one.

mowerconsultant
07-15-2010, 03:14 PM
I took an ohm reading on the clutch itself and it read 2.5-2.6 Good/Bad?

I seem to remember 4.0 being a good #, but I will have to double check.

Pj

ArTurf
07-18-2010, 10:18 PM
I just replaced the clutch with a new one. It still does not work. There is 12.5 volts going to the pigtail when the switch is on. The new clutch has the same ohm reading as the old clutch so I am guessing the old clutch is still good. What gives? What am I missing?

mowerconsultant
07-19-2010, 08:37 AM
I just replaced the clutch with a new one. It still does not work. There is 12.5 volts going to the pigtail when the switch is on. The new clutch has the same ohm reading as the old clutch so I am guessing the old clutch is still good. What gives? What am I missing?

As mentioned above, the pigtail could be your issue, did you replace it?

Pj

ArTurf
07-19-2010, 06:42 PM
Here is what I have tried in more less this order:

Checked voltage to pto at pigtail connector on pto, 12.5 volts.

Tried a new pigtail as recommended by dealer mechanic, they said voltage reading may not tell the whole story. Still nothing.

Buy new pto, try with old and new pigtail. Still nothing.

Does the pto need more than 12 volts to engage? If so why is it not getting the extra voltage?

mowerconsultant
07-21-2010, 04:38 PM
Here is what I have tried in more less this order:

Checked voltage to pto at pigtail connector on pto, 12.5 volts.

Tried a new pigtail as recommended by dealer mechanic, they said voltage reading may not tell the whole story. Still nothing.

Buy new pto, try with old and new pigtail. Still nothing.

Does the pto need more than 12 volts to engage? If so why is it not getting the extra voltage?

It really sounds like you have a ground issue some where, maybe a broken ground wire somewhere in the harness, or in a connector.
Without being there with a meter in hand testing it this is my best educated guess.

Pj

okievarmint
07-22-2010, 10:07 AM
As has been mentioned, check for ground. Better yet, jumper ground straight to the clutch and see if it engages.

ArTurf
07-27-2010, 10:25 PM
Just to let everyone know it was a relay. There are 6 found under the control panel. I bought one and changed out each one and then tried the clutch out. I found the bad one on the 2nd try.

mowerconsultant
07-28-2010, 02:45 PM
Just to let everyone know it was a relay. There are 6 found under the control panel. I bought one and changed out each one and then tried the clutch out. I found the bad one on the 2nd try.

Good to hear.

Pj

okievarmint
07-28-2010, 04:52 PM
Somethin' ain't right here. The relay supplies voltage, so if you had 12.5 volts at the clutch, the relay circuit was working.

ArTurf
07-29-2010, 11:02 AM
Somethin' ain't right here. The relay supplies voltage, so if you had 12.5 volts at the clutch, the relay circuit was working.

That's exactly the way I was thinking but apparently it does not work that way. I don't quite understand it.

Mowerconsultant: Could you explain this one to us.

Kenkirk
07-29-2010, 11:22 AM
Somethin' ain't right here. The relay supplies voltage, so if you had 12.5 volts at the clutch, the relay circuit was working.

A relay can make enough contact to supply 12 volts under no load, but under load, the contacts have developed too much resistance and the voltage will drop. In other words, under load, it cannot pass the amps at the rated 12 volts. If he had measured the voltage at the clutch as it engaged he would have noticed a voltage drop. If he pops open the relay I bet the contacts are burned.

Ken

tenndigger
06-14-2011, 11:41 AM
The clutch on my superZ quit the other day blew couple of fuses wound not engage. Friend said pigtail or new clutch but I only have 290 hours! Tried new pigtail no luck. Tested old pigtail getting 12volt power to both poles on the pigtail only 12volts to one side in the wiring harness coming from control panel. I cut apart the old pigtail and the (-) wiring connector inside the pigtail had rubbed a spot in the red wire. I put 12 volt and ground to prongs on clutch and it engages fine. I will pick up a new relay at the dealer today. It must not be getting enough voltage through the relay for the clutch to engage. Could it be anything else?

mowerconsultant
06-20-2011, 03:23 PM
How did you make out?

tenndigger
06-20-2011, 06:09 PM
I did purchase a relay the next day. I went to work on the machine and noticed that I did not fully plug the new pigtail into the wiring harness. It worked for a couple of minutes the 1st day and then quit. Corrected my oversight, put the relay in the tool box and everything works fine. I am saving the old pigtail because I can repair the short in the wire and have it for a spare.

mowerconsultant
06-29-2011, 02:16 PM
I did purchase a relay the next day. I went to work on the machine and noticed that I did not fully plug the new pigtail into the wiring harness. It worked for a couple of minutes the 1st day and then quit. Corrected my oversight, put the relay in the tool box and everything works fine. I am saving the old pigtail because I can repair the short in the wire and have it for a spare.

Ahhh.... it happens to the best of us.. lol...

tenndigger
06-29-2011, 03:32 PM
Electric clutch quit engaging yesterday. (My sons have been mowing a lot due to all the rain.) I checked the fuses-good. I immediately checked the pigtail-good. I went to the pto switch 12v going in, swith on-nothing out. Luckily I have a dealer 2 miles from my shop. Popped in new switch during lunchtime. Everything is good again. 2005 machine 300 hours.