Problems With Wearing Out The PTO Pin

[Wolfman357]

I have a Cub Lo-Boy that keeps eating PTO engagement pins. The cub has had some work done on it I'm not sure if it was rebuilt or just had a coat of paint. I have a belly mower attached but when I engage the PTO the engagement pin only last 15min before it wears down enough to make the pTO pops out of gear and the pin is worn completely flat after 15min of mowing. I've looked at the service manual to see if there's spacers missing but can't find anything missing. I read in another thread about a Bering being installed backwards. Could this be causing my problems? Because 15min shouldn't wear the pin down that bad. I've replaced the lever 4 times with the same result.







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[Gary Dotson]

It’s probably wear in the splines of the engagement collar (or clutch) or the clutch shaft causing the PTO to want to disengage. In theory, once engaged, the PTO should be quite happy to stay engaged. A taper, worn in the splines, will make it try very hard to disengage.

[Rick Spivey]

Another thought is that the set screw which holds the clutch onto the shaft may not be letting the clutch make a full travel, causing it to rub hard against the pin when engaged. Could be the set screw is too tight, or the groove it runs in has burrs, etc. Not entirely sure this would cause premature wear as the pin should have adequate clearance, but just something else to check while in there.

[Jim Becker]

A worn pilot bushing where the PTO shaft enters the transmission upper shaft may be part of the problem as well.

[Dale Finch]

My guess is that you have the older style PTO shaft with the STAKED bearing. The newer ones have a retaining clip.

The stakings get worn down and eventually allow the bearing to move forward, which allows the shaft to move rearwards. It doesn't take much movement to disengage the clutch, or start wearing down the side of the pin.

You can check by grabbing the PTO shaft or pulley and push/pull to see if there is any movement. There should be none.

This is a post of one of my rebuilds:
https://farmallcub.com/phpBB2/viewtopic.php?f=1&t=100075

[Barnyard]

Since this is the numbered series forum, I want to ask, is this a 154, 184 or a 185?

[Dale Finch]

Since this is the numbered series forum, I want to ask, is this a 154, 184 or a 185?

Shoot, I just saw LoBoy, so if it's a numbered series, my post may not apply...sorry!

[Wolfman357]

Would I need to take the belt for the mower to check for play in the PTO pully? Also how would I check for the other causes?

[staninlowerAL]

Wolfman, you need to determine and advise if you are talking about a Farmall/IH Loboy or a IH number series tractor as Barnyard asked. Otherwise you are probably not going to get correct information about your problem. JMHO Stan

[Wolfman357]

It's a Cub Lo-Boy where would I find the info on what it is?

[Barnyard]

I have moved this thread to the correct forum since it appears this is NOT a number series.

[Glen]

Hi,
Below are pics of the 2 types of Cub LoBoys, if you don't know which you have.
The 1st LoBoys were made from 1955 - 1968, they are offset, like the Farmall Cub.
Below is a page from the 1957 LoBoy operator's manual with pics.
They had different styles of hoods and grilles later.
https://farmallcub.com/rudi_cub/www.cle ... e%2003.jpg

The model of the tractor is originally on the serial number plate. If the words are weathered away, it may not be readable.

Below is a pic of a 154 LoBoy, they were made beginning in 1968, and aren't offset. The 185, and 184 are similar styles.

[Dale Finch]

Would I need to take the belt for the mower to check for play in the PTO pully? Also how would I check for the other causes?

Assuming you DO have a regular Cub LoBoy and NOT a numbered series cub, yes, you will need to remove the belt to get an accurate assessment of any fire/aft movement of the PTO shaft.

[Wolfman357]

I'll get some pics of it I was just told it was a farmall cub Lo-Boy but it doesn't look like any of the pics shown

[Wolfman357]

Here's some pics of the tractor. It seems to be the first gen because its offset like my old standard Farmall Cub.