JD 613 Cutter, Rotary PTO Shaft & Clutch

[texstrk426]

The original PTO shaft of my John Deere 613 rotary cutter (6ft. cut path) was bent due to an accident. I am trying to remove the PTO shaft end that attaches to the clutch at the gearbox. There is a locking pin on the shaft coming out of the gearbox, but removing the nut on one end does not allow me to drive the pin out. I have tried a number of times, put PT Blaster on it and pounded from the free end trying to drive the locking pin out to no avail.

There is the usual large plastic shroud over the shaft and clutch which covers up the assembly. I was able to remove a flexible ring at the front of that shroud, but the shroud will only come off if I could get to 4 bolts that hold it to the gearbox. Only two of the bolts that secure the shroud to the gearbox are accessible with the tools I have available to me. If the shroud was off, I could get easy access to the clutch and to the U-joints at the front of the clutch.

I see a cold-rolled steel pin that holds the front 1/2 of the U-joint to the PTO inner shaft. I may be able to drive that pin out and remove the shaft from the U-joint. I do have a tool that would let me remove the C-clip retainers of the U-joint cross-piece bearings. If I drove the bearings out of that front piece I could probably remove the front inner shaft along with the front part of the U-joint.

Alternatively, I could remove all the bolts that hold the Clutch together to get better access to the U-joint. If I take the clutch apart, I will have to torque the bolts & nuts when reassembling. Unfortunately I have no service information on the 613 cutter and therefore no torque specifications on the clutch bolts.

Do any of you know what the torque specifications for the JD 613 rotary cutter clutch bolts & nuts would be?

Joe

 

[Zebrafive]

Rather than a torque for the clutch bolts, you could tighten them, counting turns or flats until the large Belleville spring plate is compressed. Then when reassembling, tighten until the Belleville spring is compressed than back each nut off the number so turns or flats you counted.
That's how my Woods Brush Bull clutch is adjusted. Loosen until discs can slip. Tighten until spring plate is compressed. Back off nuts two turns. Doing it this way, disc wear does not affect the adjustment.

 

[texstrk426]

Zebrafive;

Thanks for the suggestion. It makes sense that the nuts would have to be tightened to compensate for wear. I have had this mowing attachment for around 17 years. The PTO shaft is the original to the unit.

Yesterday I took the shields off of the PTO shafts and cleaned and relubricated them. I checked for possible bends in the PTO shafts and found none using straight edge. This all began because I thought the wobble and vibration I was feeling as the mower was being operated was excessive. This was after the rocker shaft arms got stuck in far up mode. The rocker shaft valve had to be replaced and that meant it went to the dealer.

A farmer friend came over and we both evaluated the operation on the mowing unit and decided I was being too critical of its operation. My friend said that he had seen others that vibrated much more than mine. There is a possibility that when the PTO shaft was in a bind against the front edge of the mowing deck that the bolts of the clutch may have gotten bent some. I can check by looking at the outer edge of the clutch disc while rotating it by hand. If the bolts are bent, I can order some new ones through the dealer. Then your suggestion about how to make the adjustment can be followed to adjust the clutch can be used.

For now I am going to check the lubrication of the gear box and add more if needed. It may not need any as the seals have not been leaking. My friend suggested that I use 150W gear oil or higher. We are in the south and temperatures get quite high in the Summer months. The gearbox may easily exceed 140 degrees F. I think there is a drain plug for the lubricant I can remove, drain the lubricant and add new. I had been using 80W gear oil in it.

Thanks and best wishes!

Joe

 

[Tx Jim]

I've been utilizing Corn head lube(AN102562) NLGI#0 in my JD 709 rotary cutter for yrs in lieu of replacing leaking blade shaft seal.

 

[Zebrafive]

I second corn head grease!
Since you are going to a JD dealer, the service department should be able to print out slip clutch adjustment for that model.
Vibration could be blades out of balance, bent blade(s), bent blade pin, bent blade holder, bent output shaft, failed/failing bearings.