PTO engages, but, keeps becoming disengaged on LT1042.

check the "U" joints in the PTO shaft and check the splines of the PTO shaft are not seized up

Check that a wire has not been cut. Check the PTO clutch wires as well.

I’m happy to assist further over the phone at https://www.6ya.com/expert/christopher_722ea729aae6fd07

Basically your PTO is an electro magnetic clutch....when power is applied (12 volts) from the battery, the magnet is energized and the two plates come together and you have then energized your PTO clutch and it should drive the V-belt....so If you disconnect the power to the magnet the magnet becomes denergized and the two plates move away from one another ,thus the v-belt stops turning .
It could be the switch,or more than likely it is a "relay" that has gone bad ,ie, the contacts on the relay have become pitted with use and stick when they get hot from use....thus when you disengage the PTO switch the relay stays in contact thus delivering power to your PTO clutch .....if you have a wiring diagram of your unit you should be able to find the "safety or PTO relay" again this is just my theory!
If you can use a meter,you could check for voltage on the PTO wire when you disengage the PTO switch,if power is still present then we know it's an electrical issue with the switch or relay ,OR some how power is back feeding down this wire that keeps the clutch energized????? Maybe two wires making contact ????
Unfortunately a good small engine mechanic may be the way to go on this repair ......most people have a clutch that won't engage !
I hope this sheds some light on your issue ,Jim

see if there is a fuse for the clutch near the sw

check for power and ground going to the clutch if so look under the machine i have seen a few break the wires near the clutch

check the safety switches start with the one on the seat

In the cub cadet, the PTO power is maintained via a latching circuit that includes a reverse switch and a reverse relay. Locate the reverse switch that senses whether the tractor is in reverse -- either it's come loose, become misadjusted, or it's failed, or the wiring and connections are loose. You could bypass the switch to confirm this as the problem.

If its an electric PTO then the switch on the dash is bad, Its a lever type ungagement then the little break shoes that rub on the blade spindles are either worn out or mis adjusted.If it started when you changed the blade drive belt its possibly the wrong belt??

The tractor is not a 6300 is it.If it' not you need to adjust the cable for the p.t.o. until it will stay down.Don't turn the turnbuckle too much at a time because there is a fine line between the won't engage and the won,t disengage adjustment.

its actually the clutch not disengaging enough for pto to engage or the teath are worn down on pto shaft