Repairing a worn PTO shaft on cub 185

Wed May 04, 2011 8:20 pm

Hi all,
So I got my mower deck and idler pulleys bearings all fixed up now. Went to put the belt back on the PTO pulley and discovered what seemed to be way to much play vertically in the shaft. So tore it down expecting to replace the bearing at the end of the shaft. Wow! The shaft itself is worn excessivelly. Anyone else run into this problem? What was your solution if you did? I am going to drop it at my local machine shop tomorrow morning and see if he thinks he can do anything with it. I will try to include a picture. Image

Well I cant seem to add the picture so here is the link to it if you want to see it.
Last edited by Bigdog on Wed May 04, 2011 9:08 pm, edited 1 time in total.
Reason: Edited to correct photo link

Re: Repairing a worn PTO shaft on cub 185

Thu May 05, 2011 6:11 am

Your machine shop may be able to weld it up, then turn it to the proper diameter, but it won't be a cheap repair. Check with Hamilton Bob, he may have a good used one, probably cheaper than fixing that one.

Re: Repairing a worn PTO shaft on cub 185

Thu May 05, 2011 11:43 am

The shaft may be expensive. It may be easier and less expensive to just have the shaft turned from the 1 1/8 diameter to something slightly smaller. Burden Surplus sells the bearings for many different shaft sized to fit that retainer. Around $6 each.

Re: Repairing a worn PTO shaft on cub 185

Thu May 05, 2011 2:35 pm

If you carefully weld beads(lines) parallel to the shaft about 30 degrees apart then file each one flush with the rest of the shaft. The weld will be ok on the shaft and support the bearing again.

Re: Repairing a worn PTO shaft on cub 185(fixed)

Mon May 16, 2011 8:26 am

So, I got the shaft back from the machine shop, $80 to weld it up and turn it to correct diameter. Reasonable I thought. Went to put the clutch and shaft back in and learned a valuable lesson. I could not get the PTO bearing to slide onto the shaft. It just would not go on. So I live not to far from the machine shop, so i took it back thinking he did not size the shaft properly for me to drive the bearing on.

Well, guess if your stupid you might as well show iT! My machinest showed me how the PTO bearing is acutually a cam lock bearing, (NEVER HEARD OF ONE), he showed me how to turn the lock collar so it would slide onto the shaft then using a punch turn it in the opposited direction of the shaft travel to lock it on the shaft. Then tighten the set screw to secure it in the locked position.

No doubt the PO had obvousily replaced the bearing and never locked it on the shaft with the cam collar. Thus creating the wear area you can see on my shaft prior to having it welded and turned. I am sure all of you cub pro's probably were aware of how to do this but this was my first experience with a cam lock bearing. Take care all and hopefully it will stop raining in the NE soon enough to mow some grass now.

Re: Repairing a worn PTO shaft on cub 185

Mon May 16, 2011 10:16 am

The cam lock bearing work well in securing the bearing from movement. Typically you would lock by turning the lock collar in the direction the shaft turns not the opposite of the shaft direction. It will lock either way but will stay be less likely to loosen when punched in the direction the shaft rotates.

Re: Repairing a worn PTO shaft on cub 185

Mon May 16, 2011 12:29 pm

An unwritten rule of thumb within our company (we install them by the 100's) is to tighten them in the direction of rotation, then the technician later on, if it needs removal, knows which direction to loosen the collar. Experience also indicates, that if a new collar was installed by someone else, to look for the direction it was tightened by the distortion in the holes.. (a re-used collar...toss-up)

Re: Repairing a worn PTO shaft on cub 185

Mon May 16, 2011 12:41 pm

Interesting comments, thanks guys. I would add that if you rotate the collar in the same direction as the rotation of the shaft, then it possiby could work itself loose with inertia. If it was rotated to the opposite direction it would only get tighter with time, never looser. So I just wonder why it is recommended to tighten it the same direction unless it is just a service recommendation as noted above so the future technician knows which way to loosen it. Maybe the bearing and cam collar should have marks on the so you can tell which way is loose and which way is tight?

Re: Repairing a worn PTO shaft on cub 185

Mon May 16, 2011 1:18 pm

Just the opposite, IMHO..The setscrew fastens the collar to the shaft, locking in the direction of rotation ensures that the collar is constantly tightened should the bearing try to spin on the shaft.
Is confusing, though..