PTO clutch quit working

[02chuck1]

Now that the mower runs, I took it out to test drive it. After mowing for a while I stopped the blades while backing up and when pulling the switch the clutch did not engage.
Back in the shop with the engine off I heard a click from under the mower. With my wife turning on the blade from the switch I noticed that the clutch clicks and pulls up a small amount, but does not engage.
So does this mean the clutch is toast and time to buy another one or are there ways to salvage what I have?
Thanks for the help
Chuck

 

[oldnslo]

What make and model of mower. Some models have an air gap adjustment on the clutch. Typically this style clutch has 3 or 4 bolts with springs around them and slots in the housing between the bolts. to check air gap slide a feeler gauge in the slots between the clutch plates. air gap should be .010 inch. To make this adjustment slide a feeler gauge in the slot then tighten the nuts evenly until feeler gauge is snug. Make sure that you tighten all the bolts evenly and check gap in all of the slots.

 

[02chuck1]

Sorry on not putting in type.
John Deere 145 22hp twin.
Pulled Clutch, do not see any adjustment bolts.
I googled adjustment and repair of this model and all I found was R&R .
Thanks
Chuck

 

[oldnslo]

Chuck,
If it was working before backing up then I would start checking to see if you have the full 12 volts getting to the clutch. Possible some connection between the switch and clutch is loose or slightly corroded causing limited voltage to reach the coil. Presuming this model has reverse safety feature that stops the deck, could also be something in that circuit.

Another simple check is the resistance of the coil on the clutch. Using an ohm meter test the clutch coil resistance by unplugging the wire and then placing the leads from the volt ohm meter on the connectors to the clutch. Not sure what the reading is for your 145 but as a point of reference my X540 the reading is 2.8 - 3.3 ohms.

More difficult test is the clutch coil amp draw. This requires an amp meter capable of 10 amps with slo blow fuse to handle the in-rush current. Actual amperage is typically in the 3.5 to 4.5 amps range. Again not 100% certain what the 145 specs are.

hope some of these ideas help.

 

[02chuck1]

Thanks for the trouble shooting ideas, I'll give it a try in the morning.
Chuck

 

[mwayne]

My brother had a mower like that with a similar issue, the problem was the switch contacts had overheated and melted and weren't passing enough current to magnetize the coil. If you can, try to feed the clutch straight from the battery to see if that works.

 

[02chuck1]

Another option to check
Thanks
Chuck

 

[RoyJackson]

Can't comment exactly on your mower, but I can say the PTO switch on the ZTR's is a weak point. I've replaced mine (Z920 ZTR) twice...my neighbor (Z930) has done the same.
Might be the same switch...
BTW, replacements are cheaper on Amazon

 

[02chuck1]

Thanks
C

 

[02chuck1]

Trouble shot the system. Had 12.5vdc when the switch was engaged and found 0.5 ohms when metering the clutch. So bought a clutch.
Installed new clutch yesterday and it works once again.
Bought the clutch from xtremeope.com price was good and the installation directions were great.
I'll let you know how it works out.
Chuck