PTO won't stop

[PeterE]

I recently bought a 730 diesel.

I can use the master switch on the floor to change the PTO state (when the engine is off, of course). When that switch is off, the PTO is off.

When the switch is on, the PTO is ALWAYS on. It doesn't matter where I position the foot-pedal. I thought maybe the foot-pedal connecting rods were out of alignment, so I pushed around the lever at the rear it connects to. Still no luck in turning it off.

Any thoughts?

 

[Bob]

The PTO clutch/ is mis-adjusted, or the $$$$ clutch plates are warped, doubled up, or otherwise mangled.

 

[Jared K]

Another possibility is that the brake is not adjusted properly.

 

[Bob]

The PTO clutch/brake is mis-adjusted, or the $$$$ clutch plates are warped, doubled up, or otherwise mangled.

("brake" was supposred to be next to the / in the first post!)

 

[Machinery-Man]

sounds like someone has tightened the pto to the point it is not releasing properly. Maybe they did this for a sale job....anyway I"d back off the adjustment some and see if releases, also would change the fluid in the pto, anything except going in there with new disc $$$$$$$$requires a boat load of money. Most of the time the horseup 730 really put a twist on the clutches. Good luck...Chuck

 

[Mike M]

Don't forget to check the pto oil. I'm betting it is getting gear oil in from the tranny too. Which is not good. This will put too much drag on the parts inside and is too slippery and burn them up under load.

That foot pedal should have a plate with a definite notch in it ( most are worn out ) that it snaps into when pushed down on the pedal. Make sure yours snaps into this notch and you adjust the rod clevis back by the pto units arm. It does take some pressure to stop these.You won't be able to get enough by pulling with your hand on the lever.

 

[PeterE]

Thank you very much. That is about what I feared. I was hoping it was something stupid/simple like another switch somewhere.

 

[wilamayb]

I fear the worst for you. It's as the others said the oil from the trans/rearend is possibly entering the PTO housing. My advise would be to drain it for a look see. If you are not sure if the oils are mixing just leave a pan under it over night to see if it leaves you a pool. That cavity should be filled with 10W engine oil, but J20C hyguard is also very good if you already have some on hand.

If you find that the oil has not been transfering then perhaps you will just have to replace the metal plates unless your clutch material has fallen off the discs (happens from prolonged exposure to gear oil or water). Many times I've found that the plates are warped from the previous installation. If the plates are not lined up perfectly it is a pain in the rear to get them in the drive hub, which is why many of them are bent when folks force them into the housing. I use an old hub out of a junk tractor to line the plates up on the bench. It helps!! You may want to look into getting one for youself. That PTO assyembly gets heavy while you are tryng to hold it up and align the plates at the same time. Whew! You can count on needing a new brake plate if it has been running all the time in the off position. The most exciting thing is that the brake plate is on the end of the assyembly, so it all has to come apart.

Good luck with the new 730!! PTO clutch/brake is something that most of us have done! Its one of those normal things for a two cylinder with live power. I have not done one for a while, but I recently bought a 720D std. black dash that has a PTO braking problem as well. I'm gonna do it in my spare time. LOL!

 

[2cylinderlp]

The others covered it pretty well I think. Here is a picture of mine as it was rebuilt. The clutch is engaged which holds everything lined up to put it in the tractor. The cage which surrounds the clutch pack (not in this pic) has to come out to replace the seal that keeps the tranny lube out of the pto. You can't get at that seal without taking the whole rear housing containing the rockshafts off. IMHO every John Deere tractor that has that type of seal, should have it replaced to save the expensive PTO clutch. (unless you know it has been done of course) It really is a case of preventive maintenance that is worth the effort. Potential screwups would include forgetting the fiber thrust washer and putting the brake plate on backwards. I've done two of these and they both had broken springs inside of this assembly. The brake is adjusted by changing the effective length of the engagement rod that runs back from the pedal. When you roll the foot pedal back to release the clutch, it won't apply the brake without a little extra push to lock the brake. When you put this whole business back together, the clutch adjustment is estimated for assembly and then fine tuned once you have it all in there. Adjustment is accessed through a small cover down on the right side. The adjustment itself is a bit of a puzzle until you have done it once. Yours could be too tight as some have said, and then the brake just not adjusted tight enough. (if you are lucky) I got some of my parts from Weber Tractor Repair. They were great to deal with.
http://www.wtrparts.com/

 

[2cylinderlp]

Picture didn't post, try this

 

[2cylinderlp]

Well I got the wrong pic. Here is the other one.

 

[Mike M]

I was thinking the brake plate I last got had facings on both sides ? It subbed numbers alot from original and this was a long time ago too.

 

[2cylinderlp]

They do on a 530, but I guess not on the 730. Not sure about a 630. I'll be finding out on a 630 project that I have coming up. I questioned if that one sided brake was correct and even called Weber's about it. My understanding now is that the brake facing is only on one side on the 730. Now that I have mine in and adjusted, it seems to work very well.

 

[Mike M]

I thought all those parts were the same ? you just add more plates to the main clutch as the HP goes up.

 

[2cylinderlp]

Well I'm comparing the parts book on 530 and 730. The brake plate definitely has different part numbers. As I go down the parts lists it seems like there are more differences than similarities. The gears, bearings, shafts, and even some of the springs are all different. The clutch plates themselves are the same. I found this assembly to be a bit of a mechanical challenge. Getting it back together was a mini-victory for me, (as Roger Welsh would say).