Trouble with PTO clutch staying on when in run position
 

If you guys saw my previous thread of installing the Magnum 15 into a 1864, I managed to start up and run the magnum and am now experiencing a PTO clutch that will start up in the start position, but not stay running in the on position. So far I checked the reverse switch plug and noticed it was jumpered out as is the seat switch plug. I tried switching out the PTO relay with the spare one I had. I also swapped out the PTO switch with the other switch I had. Last thing I did was to swap out the PTO clutch with a know good clutch that came off a KT 17 series II engine. The clutch is still acting the same, comes on start position but does'nt stay on " on " position. Anyone have a clue?

The engine doesn't need to be running for these tests.

Are you getting power on the red/white wire on the reverse relay(terminal 30) with the ignition switch in the "on" position? Also check it with the PTO switch in the on & off position. There should always be 12 volts there with the key on.

Are you getting power on the black wire (terminal 66) with the PTO on and seat switch jumped out(for testing) or someone sitting in the seat?

I will check those out. Thankyou for your response.

With ignition key turned to on, checked out the red and white at terminal 30 and had 12 volts but the black at terminal 86 did not.

Even with PTO switch in on position, still not getting 12 volts at terminal 86.

Key on, engine off, move PTO switch to start and then on for this test.

Is there 12vdc on the violet wire at the seat switch?

No there is not 12volts at the seat switch.

That violet wire comes from the "B" terminal on the PTO switch and should have 12 volts on it when the switch is on. Either your wire is broken or the switch or plug is bad.

This is true if your relay and other wiring are good which they should be if it starts in the start position. I would start doing continuity checks on your wiring to confirm the PO installed jumpers are installed correctly........for test purposes only.

Ok Oak, I will test for 12 v at the PTO switch and start testing continuity at the wires. Thanks for your response.

Just checked the purple wire terminal at the switch with switch turned on and no 12v. Looks like I will be ordering a new switch. Where is a good place to order a new PTO switch?

Ok, at this point I installed a new PTO switch and with the switch on start position I'm reading 11.92 volts at the harness plug, purple wire for the seat switch. With the switch in on position, I'm reading 0 volts. I checked continuity on the black wire comming back from the harness plug for the seat switch and it shows good continuity. Why would I not see 12 volts on that purple wire with the switch in on position?

Good news. I was looking at the wiring schematic and noticed the reverse relay in order to have the relay energized, needed to see a ground at the gray wire
(terminal 85 ). So I checked for that ground and did not see it. So I made up a connection from terminal 85 to ground and was able to run the PTO on the "on" position.

Do you have a URL for the schematic handy? I'm horrible at reading them, but guess I need to.

My Cub has all the safety crap bypassed by the PO. PTO worked last fall, and this spring will not stay on.

-- I can turn the PTO on, but it will not STAY on. I can hold the PTO switch on with a Vice Grip (and need to today so I can mow before I have to bale)

It's possible I bumped something when I rebuilt my steering pump, but unless a mouse chewed something I can't see....

Found my fuse issue, I had a 1.5a, not 15 amp. I guess I need cheaters finally..

Also, I checked and I do not have a violet wire in my PTO switch bundle. Is there a way to just install a simple on/of switch?

:bash2:

What model cub do you have?

I've got the 1872.

I did locate the relay last night, and now I am seeking the pin-out and what I should be touching to see if +12 excites it. I just did this with an old Cushman with an ignition issue, but that was a current-style relay with the diagram on it.

I will say, even having to hold the switch in the start pos last night, I was able to get in an evening of mowing with no new leaks in my steering, which made me so happy!

CUBCADETPARTSNMORE.COM has the schematic for your tractor, I just downloaded it and made a copy. It looks like you do not have the purple wire like I did on my pto switch. You have a brown wire that goes to your reverse switch then it continues to the seat switch and a brown return wire to the reverse relay that grounds out when the relay energizes. Check the black wire at the reverse relay to make sure it shows a ground to the frame. I would also check for continuity in the brown wire from the pto switch all the way to the reverse relay.

The white wire that hooks up to your reverse relay comes from the engine alternator and once the reverse relay energizes it sends 12 volts through the black wire at that same relay, over to your pto. So you should be seeing 12 volts at the brown wire and also 12 volts at the white wire, at your reverse relay and also 12 volts at the black wire comming out of the relay on to your pto.

forgot to mention, The two 12 volt above conditions should only exist if your sitting in your seat and not going in reverse.

Thanks. I have no reverse or seat safety in the mix, they have been removed from the previous owner. I assume the 'reverse relay' mentioned is the 3" long enclosure bolted to the left side of the frame behind the side panel.

I would guess that your relay looks like a typical relay, black plastic outside about 1 1/4 square inches with 5 or 6 spade terminals on the bottom to connect your wires to. Do you have a ohm meter to do your testing with? Not really sure where they placed the pto relay on your 1872.

This is what I have on my cubby. Old school, nothing plastic
https://www.ihccw.com/image/cache/ca..._1-450x450.JPG

No safety's, nothing. all bypassed heh.

Those good metal cased HD relays were sourced from Delco Remy, and were used on GM vehicles for A/C high speed blower motor fan relays and headlight door relays on hideaway headlight cars.

They don't fail often. Typically, either the seat switch or reverse switch/circuits are to blame for the issue you are experiencing.

I do not have any of the safety items, they were all removed prior to us owning it. "ran when parked' best fits my case HAH.

Were you able to do any testing at that pto relay to make sure you have the 12 volts at both the brown and white wires?

I have +12 on the white, nothing on the brown.