PTO/Clutch Issue

[bamadirtrider]

Friend has a SCAG Tiger Cat 61. Switched the PTO on and blew a 20 amp fuse on the right fuel cell Immediately. Didn't actuate the deck at all. Replaced it and blew again with no deck action. Put another fuse in so he could get it home(Its cranks up & drives no problem).
He then placed another 20 amp in, flipped the PTO switch on and blew the fuse. OHM'ed the clutch - 0.0. Put 12 volts to the clutch and it actuated. Reattached the wires and put a 25 amp fuse in and switched the PTO on and the blades turned as advertised. Only left it engaged for a couple seconds so he wouldn't burn anything. We are stumped: How does the clutch OHM a 0.0 and blow normal fuse & yet will work with a higher rated fuse?? And any suggestions for a fix is appreciated.
TIA

 

[StarTech]

Once you get down to under 1 ohm its takes a milliohms meter to measure that and most el cheapo meters simply can't read accurately this low.

But yes a clutch that is partially shorted can still operate but will over the charging system and a lot of the time start melting connector and burn off wire insulation. That PTO clutch should not be pulling more 7 amps at the most so install a 7.5 amp inline with the clutch and if blows replace the clutch.

 

[Its Me]

Tell your friend not to cut all the way to the roots of the grass, slow the froward speed down, that will lengthen the life of the clutch, they get to hot, slip, both of those build up head and then the problems start showing up, that clutch should last many years if used as designed.

 

[Tiger Small Engine]

Once you get down to under 1 ohm its takes a milliohms meter to measure that and most el cheapo meters simply can't read accurately this low.

But yes a clutch that is partially shorted can still operate but will over the charging system and a lot of the time start melting connector and burn off wire insulation. That PTO clutch should not be pulling more 7 amps at the most so install a 7.5 amp inline with the clutch and if blows replace the clutch.

Most PTO clutches should be between 2-4 ohms when checking with a multimeter. Could be wires that are worn and shorting out to ground. Check wiring and repair wiring or replace PTO clutch. What is age of Scag and hour meter reading?

 

[bamadirtrider]

Most PTO clutches should be between 2-4 ohms when checking with a multimeter. Could be wires that are worn and shorting out to ground. Check wiring and repair wiring or replace PTO clutch. What is age of Scag and hour meter reading?

5 years and just over 500 hours.

 

[bamadirtrider]

Tell your friend not to cut all the way to the roots of the grass, slow the froward speed down, that will lengthen the life of the clutch, they get to hot, slip, both of those build up head and then the problems start showing up, that clutch should last many years if used as designed.

He only cuts to 2.5 inches and never lets grass grow long. The company he retired from hired him to maintain the landscape and pay him by the hour so as to speed . . . LOL.

 

[RevB]

Friend has a SCAG Tiger Cat 61. Switched the PTO on and blew a 20 amp fuse on the right fuel cell Immediately. Didn't actuate the deck at all. Replaced it and blew again with no deck action. Put another fuse in so he could get it home(Its cranks up & drives no problem).
He then placed another 20 amp in, flipped the PTO switch on and blew the fuse. OHM'ed the clutch - 0.0. Put 12 volts to the clutch and it actuated. Reattached the wires and put a 25 amp fuse in and switched the PTO on and the blades turned as advertised. Only left it engaged for a couple seconds so he wouldn't burn anything. We are stumped: How does the clutch OHM a 0.0 and blow normal fuse & yet will work with a higher rated fuse?? And any suggestions for a fix is appreciated.
TIA

Imagine a face palm image right about here. Put in another fuse? Damn thing is trying to tell you something is shorted but, no, put in another one just to make sure. Then another. Then one with a higher amperage. Let's burn up the damn wiring too. Speaking of which...stop fixating on the clutch now, look at the wiring and connectors.

 

[StarTech]

Imagine a face palm image right about here. Put in another fuse? Damn thing is trying to tell you something is shorted but, no, put in another one just to make sure. Then another. Then one with a higher amperage. Let's burn up the damn wiring too. Speaking of which...stop fixating on the clutch now, look at the wiring and connectors.

This a 7.5 amp should be installed in all PTO clutch wiring harnesses so when one is partially shorted it blew that fuse. I have replace a lot melted connector housings because some just larger and larger fuses.

I even had that told me go jump in the lake because the clutch was still working and that he would not replace that expensive item. Well his mower looked like this the other day.

Was it worth it not listening someone that knew better?

 

[RevB]

This a 7.5 amp should be installed in all PTO clutch wiring harnesses so when one is partially shorted it blew that fuse. I have replace a lot melted connector housings because some just larger and larger fuses.

I even had that told me go jump in the lake because the clutch was still working and that he would not replace that expensive item. Well his mower looked like this the other day.
View attachment 68068
Was it worth it not listening someone that knew better?

Non-electron familiar folks think fuses protect the device. Nope. They protect the wiring to the device.

 

[bamadirtrider]

Imagine a face palm image right about here. Put in another fuse? Damn thing is trying to tell you something is shorted but, no, put in another one just to make sure. Then another. Then one with a higher amperage. Let's burn up the damn wiring too. Speaking of which...stop fixating on the clutch now, look at the wiring and connectors.

Certainly appreciate all that helpful information! Had I wanted to get blistered like that I would have attended a Don Rickles show and sat right down front. If you need help in how to just roll on by a post you have an issue with and can't use a civil tone I can carve out about 6 months to teach you as that May just be enuf!
Bugger off!