Pto randomly shuts off

ironheadchop

Forum Newbie
Joined
Sep 18, 2022
Threads
2
Messages
4
Having an issue with my Zforce SX 54. When im mowing the pto just randomly turns off. Like something is loose. Everything feels tight like it should. Anyone else have this happen or have suggestions on what to check?
 

StarTech

Lawn Royalty
Top Poster Of Month
Joined
Feb 19, 2020
Threads
75
Messages
10,110
Probably a bad PTO switch like the one I replaced earlier this year that was doing the same thing. Could cycle the switch and PTO worked for several minutes before stopping again.

Also check current draw of the PTO clutch windings. Should not be pulling more than 7 amps max.
 

ironheadchop

Forum Newbie
Joined
Sep 18, 2022
Threads
2
Messages
4
Probably a bad PTO switch like the one I replaced earlier this year that was doing the same thing. Could cycle the switch and PTO worked for several minutes before stopping again.

Also check current draw of the PTO clutch windings. Should not be pulling more than 7 amps max.
Where do i check the draw at?
 

StarTech

Lawn Royalty
Top Poster Of Month
Joined
Feb 19, 2020
Threads
75
Messages
10,110
Depends if your have a clamp meter or the one that must hardwired into the clutch circuit.

If you don't either then install a 7.5 amp fuse in one of the wires going to the PTO clutch (Hint: there is only two wires). Once you power up the clutch if the fuse blows the clutch is partially shorted and must be replaced.
 

shadetree#1

Well-Known Member
Joined
Oct 31, 2022
Threads
1
Messages
153
The seat switch will cause such.
 

shadetree#1

Well-Known Member
Joined
Oct 31, 2022
Threads
1
Messages
153
I did not read all of this post but as StarTech indicates you can bypass all the SAFETY SWITCH and install a 7.5-10 fuse directly in either wire going to the electric clutch and connect the clutch wiring directly to the battery.
If it then cuts on and off you know it's the clutch itself.
Just be aware that all the safety switch are bypassed.
I would install a on-off switch in the pos 12v wire that can be operated from the driver seat..
 

StarTech

Lawn Royalty
Top Poster Of Month
Joined
Feb 19, 2020
Threads
75
Messages
10,110
I did not say (type) anything about bypassing any of the safeties. Period. Just about installing a 7.5 amp fuse inline to test the clutch to see if it is drawing excessive current. A PTO clutch drawing excessive current can damage the PTO and ignition switches. Most of the PTO switches are only rated for 5 amp current draw.

Either way I would perfer if the OP used an actual amp test meter. Just most DVMM will only test up to 10 amps before they are destroyed as they are unfused at this level.

I have seen melted connectors and wiring where clutches were pulling over 16 amps and still be operating.
 

dana a

Active Member
Joined
Sep 6, 2016
Threads
7
Messages
94
I did not say (type) anything about bypassing any of the safeties. Period. Just about installing a 7.5 amp fuse inline to test the clutch to see if it is drawing excessive current. A PTO clutch drawing excessive current can damage the PTO and ignition switches. Most of the PTO switches are only rated for 5 amp current draw.

Either way I would perfer if the OP used an actual amp test meter. Just most DVMM will only test up to 10 amps before they are destroyed as they are unfused at this level.

I have seen melted connectors and wiring where clutches were pulling over 16 amps and still be operating.
If the clutch was drawing say 10 amps would that burn out the 5 amp PTO switch or does it have a circut breaker in it? I'm thinking if ironhead did run a wire from the battery to the clutch with a 7.5 amp fuse in line that would definitely tell if the clutch was the problem or not. Can you see it that way or should that not be done at all?
 

StarTech

Lawn Royalty
Top Poster Of Month
Joined
Feb 19, 2020
Threads
75
Messages
10,110
If the clutch was drawing say 10 amps would that burn out the 5 amp PTO switch or does it have a circut breaker in it? I'm thinking if ironhead did run a wire from the battery to the clutch with a 7.5 amp fuse in line that would definitely tell if the clutch was the problem or not. Can you see it that way or should that not be done at all?
Yes drawing 10 amps will melt down the terminal mounts. That is why I replace so many PTO switches.

As long as it is for test purposes only then it is okay but not as a permament fix.
 
Top