Cub Cadet PTO Problem

[lefty]

Cub Cadet
2166
13A-254G100

This is my first PTO issue to deal with. The switch does nothing when actuated. A preliminary visual inspection of the wiring reveals nothing out of the ordinary such as wire damage. The testing I've done thus far: The switch itself. I found some instructions on how to test that and it seems to test OK. I also put 12V to the PTO and I'm having trouble decerning if I'm getting an acceptable result. It's making a noise but it's not a clicking noise that sounds like something mechanical is occuring. It almost sounds like it's trying to move something immovable. I don't know how to describe the sound exactly but something tells me it's not the sound I'm looking for.

A couple of notes:
1. There is a green wire behind the bulkhead coming up from the harness with a ring terminal that is just hanging out. It may be a ground that terminates at screw (4) and washer (15) on the Bulkhead, Dash, Panel, and Engine Controls diagram as the screw (4) was missing. Washer (15) was just laying on the frame and mounting rod (18) was just dangling. But this is a guess and I don't think it matters because I tested the PTO while grounding that wire...No joy. I know it was connected somewhere because it is worn in such a fashion that would indicate it was connected to something.

2. I'm not sure if this is related but the ignition switch is also acting wonky. The engine will not shut down when I turn the key to the off position with the engine at low RPM's. It will kind of act like it wants to but keeps catching. Wiggling the key doesn't help but if I try to shut it off at full throttle, it will shut down. I know...very weird.

The engine starts fine and everything seems ok on that front. I'd like to test the PTO itself but am not sure what to look for at the connector. Any advice/ next steps are appreciated.

Thank you

[lefty]

A little more info on this that may be helpful...the owner reported that he got on it one day and the PTO wouldn't work. It suddenly at some point after that started working again and then cut out during mowing, which is the last time it worked.

This machine is very interesting, to me anyway. It has a solid drive shaft from the engine back to the transmission. The PTO is mounted on the front of the engine, horizontal shaft. The belt then twists and each side goes down to hit a perpendicularly mounted pulley on either side. The belt twists again and heads to the deck pulley. For what it's worth, the belt is super tight. I mean really tight. Maybe by design but I've never seen a belt that tight. It puts quite a bit of stress on every pulley, including the PTO pulley.

Thanks

[KE4AVB]

First in downloads there is a link to wiring schematics, IPLs, and service manuals for the Cub Cadet mowers.

If the Clutch attempts to engage it may be partially shorted or could even part of a belt cord jammed in it. Yes it is possible as I have remove kevlar cords from these clutches before.

Also on the deck check that double stack pulley for bad bearings. They are 6203-2RS5/8 bearings. Cub Cadet wants $26 a piece for the bearings but you should be able acquire them otherwise. Also that pulley is $103 as a customer here just found out because he let the bearing to completely fail. I mean one was locked up and the other lost the balls and the outer ring.

The deck drive belt is B x 112.5" Kevlar.

Electrically check the Packard (F56, Delphi) terminals as their spring hinges do break leading to loose connections.

[bgsengine]

Cub Cadet
2166
13A-254G100

This is my first PTO issue to deal with. The switch does nothing when actuated. A preliminary visual inspection of the wiring reveals nothing out of the ordinary such as wire damage. The testing I've done thus far: The switch itself. I found some instructions on how to test that and it seems to test OK. I also put 12V to the PTO and I'm having trouble decerning if I'm getting an acceptable result. It's making a noise but it's not a clicking noise that sounds like something mechanical is occuring. It almost sounds like it's trying to move something immovable. I don't know how to describe the sound exactly but something tells me it's not the sound I'm looking for.

A couple of notes:
1. There is a green wire behind the bulkhead coming up from the harness with a ring terminal that is just hanging out. It may be a ground that terminates at screw (4) and washer (15) on the Bulkhead, Dash, Panel, and Engine Controls diagram as the screw (4) was missing. Washer (15) was just laying on the frame and mounting rod (18) was just dangling. But this is a guess and I don't think it matters because I tested the PTO while grounding that wire...No joy. I know it was connected somewhere because it is worn in such a fashion that would indicate it was connected to something.

2. I'm not sure if this is related but the ignition switch is also acting wonky. The engine will not shut down when I turn the key to the off position with the engine at low RPM's. It will kind of act like it wants to but keeps catching. Wiggling the key doesn't help but if I try to shut it off at full throttle, it will shut down. I know...very weird.

The engine starts fine and everything seems ok on that front. I'd like to test the PTO itself but am not sure what to look for at the connector. Any advice/ next steps are appreciated.

Thank you

Methinks if you hook up your green wire to ground you might possibly solve the no-shut-off problem.. sounds like your switch is not getting magneto grounded, but it is shutting off the afterfire solenoid (which is why it kills at off-idle/full throttle, but may keep running at idle, as fuel will still feed through idle circuits)

Second, as far as your PTO - when you switch it on to see if it works, take a screwdriver close to the clutch plate (between the pto pulley and the engine) if it grabs your screwdriver, then it is probably electrically OK, but your clutch plate may be jammed or out of adjustment (does this unit have triangular shaped PTO bracket with fine thread 3/8 nuts , and springs behind the plate on those studs the nuts are on? If so, then it is adjustable, and check if you have a .010 - .012 gap)

[bgsengine]

This machine is very interesting, to me anyway. It has a solid drive shaft from the engine back to the transmission. The PTO is mounted on the front of the engine, horizontal shaft. The belt then twists and each side goes down to hit a perpendicularly mounted pulley on either side. The belt twists again and heads to the deck pulley. For what it's worth, the belt is super tight. I mean really tight. Maybe by design but I've never seen a belt that tight. It puts quite a bit of stress on every pulley, including the PTO pulley.

Thanks

I used to work on these all the time (daily, worked at a cubby dealer before and during when MTD bought them) Yes the belt is tight - check on deck - some decks will have a tensioning lever you can release to let off belt tension (on the left side of deck, from operator seat) - others will have a square drive notch in the tensioner bracket on the deck that you can put a 3/8 or 1/2 drive ratchet or breaker bar into to release belt tension..

ALSO_ if you EVER have the belt off, make damn sure you realize and know about the belt guide - a single (3/16") bent wire that bolts to right side of the bracket that holds the front pulleys (it is called a mule drive, BTW and has a quick attach lever up front for easy removal) but that belt guide wire was the SINGLE most common cause of deck drive belt failure on those I ever saw - People didn't realize (or forgot) it was there, and they ran their belt OVER the guide, jamming it between the pulley and belt.. Most often the wire broke away, or bent but often it didn't bend far enough away and the end of the guide just dragged along the edge of the belt ripping it to shreds.. If there is not one on yours, it likely was either removed, broken, or missing (look for empty bolt hole, or a bolt that holds a useless ring of wire - also look carefully for the guide wire as when it gets whipped out of the way it can often be hard to really see it til you take mule drive off)

[lefty]

Thank you. I'm going to take all of this info when I attack it some more today.

[lefty]

I think it may be a bad PTO. I have continuity between the blue wire to the PTO and the switch, as well as continuity between the opposing pin and ground. There is also continuity between the red wire at the PTO and the positive terminal. Switch tests good. So I was thinking that there could be a fault behind the switch but I watched a video on how the PTO is supposed to operate and inspected it closer. It looks like when the machine is off, one 1/2 of the plate is stuck like it's being drawn toward the engaged position by magnetism. The other side is being drawn out by the spring toward the brake.

I put 12V to the PTO again after watching a video about how the PTO should be working and I see no movement of the plate when applying a voltage directly from the battery. It looks like it's trying to move but can't. My assumption is that this means the PTO is fouled up somehow. I haven't found the specs yet but the resistance on the PTO was 4 ohms. I'm going to keep reading the suggested materials and working on it but thought I'd post back with where I am at this point.

Thanks.

[lefty]

Here's some imagery.

https://youtu.be/doqaVa61vfE

[lefty]

Methinks if you hook up your green wire to ground you might possibly solve the no-shut-off problem.. sounds like your switch is not getting magneto grounded, but it is shutting off the afterfire solenoid (which is why it kills at off-idle/full throttle, but may keep running at idle, as fuel will still feed through idle circuits)

Second, as far as your PTO - when you switch it on to see if it works, take a screwdriver close to the clutch plate (between the pto pulley and the engine) if it grabs your screwdriver, then it is probably electrically OK, but your clutch plate may be jammed or out of adjustment (does this unit have triangular shaped PTO bracket with fine thread 3/8 nuts , and springs behind the plate on those studs the nuts are on? If so, then it is adjustable, and check if you have a .010 - .012 gap)

That was the case. The green wire was the problem with shutting down. Thanks. The clutch does not appear to be adjustable but it does appear to be stuck. I tried to operate it and it acts as if it's stuck but I did put a screwdriver in there and it seems like the magnet is not strong enough to pull the plate in. Both when energized and when not engergized the plate looks as if it is being drawn in on one side and the other side is pressed against the brake. I can pull it away from either side by prying with my fingers or a screwdriver but it snaps back into this cocked position whether there is power to it or not. I don't see any springs or nuts for adjusting on the sides but I think I know what you're talking about because my personal z-turn has the one you're referring to, I think. This one is more round.

I see almost no movement at all when putting power to it. I'm no longer even hearing any noise like had had initially described.

[bgsengine]

sounds like worn out clutch - the brake plate after so many hours may tend to wear away (more so in dusty areas) and eventually the air gap between clutch plate and clutch drive is just too much for the magnetism to pull in the clutch - one test you can try - engine NOT running, engage PTO and use your screwdriver see if you can wiggle the clutch plate in closer to the magnet if it snaps into engaged position as you move it closer, that's probably just a worn out clutch - only fix is a new clutch .. Other thing to check is make sure there's solid ground between PTO clutch and B- (perhaps a jumper wire to test?) - if that cubby sits on vibration isolator mounts, they do have a ground strap between engine cradle and frame that frequently will go bad...