PTO clutch rebuild

Thu May 24, 2012 9:04 am

I am rebuilding the pto clutch in a LoBoy 185. The manual says there should be a thickness difference of 0.050" between the disengaged and engaged positions and to add spacers to obtain that difference. Without any spacers at all I get about 0.017". When I add any spacers to increase that distance, the friction plates are locked down even in the disengaged position so that the clutch would never disengage.
I am using all new friction plates which are quite a bit thicker than the old ones (which seems normal) but I am puzzled by why they are so tightly held in the disengaged position. The wavy springs are in place as they should be, but is it possible that the wavy springs are not forcing the friction plates apart as they should?
I've rebuilt several of these clutches before but this one has me stumped.

Re: PTO clutch rebuild

Sat May 26, 2012 6:59 am

There is a metal ring spacer, about 1/4" thick, that sits in front of the forward cam, right before the rear PTO Flywheel. For some reason, I have seen them in different thicknesses. If you grind down the ring thickness, carefull to keep it square, you will free up room for more clearance for spacers.

Re: PTO clutch rebuild

Sat May 26, 2012 8:45 am

Thanks for the tip. I went back and looked at that spacer and it appears not to be an "original" part, probably home-made by someone. I'm guessing someone before me tried to rebuild the clutch and put in a thicker spacer to make up for the wear on the old friction rings.
Bob, as always, you are right on the money with expert advise. Thanks very much for sharing your knowledge.