Belleville washers for Kubota RC60-24B mower deck

victor43 · Jul 15, 2016

I have a RC60-24B mid mount mower deck on my 1996 B2400hsd tractor. At the last blade change, I noticed that the Belleville cupped washers that are under the bolt that holds the blades to the spindles are completely flat. Having no problems with blade spinning, but thought it would be a good idea to replace the washers. However, I don't want to pay dealer prices. I can't find a parts list for the mower deck. Could measure the washers I have, but when I look for new washers, the specify ID, OD, material, thickness, height of cupping etc. How can I find the correct washers? Does anyone have the Kubota part number? Would appreciate information on how other owners have gotten the correct replacement washers.

dgraves49 · Jul 15, 2016

Don't know the measurements but when I recently got new ones for my RCK60 they were only $3.65 each from the dealer.

jeff9366 · Jul 15, 2016

Bay usually offers a pretty good assortment of Belleville cupped washers.

Mysfyt · Jul 16, 2016

McMaster Carr has an excellent supply of these. You should find some that will work much cheaper than dealer price.

dgraves49 · Jul 16, 2016

Checked the packaging from the ones I purchase. The ID is 23mm, The od is 2 inches, and they are about 3/32 inch thick. When looking for them don't forget to figure shipping in the cost. If you have a dealer nearby they probably have them in stock or can have them sent in with their regular stock order so you wont have shipping cost to pay.
The Kubota 3 for my RCK60-23BX is K5371-34352. I would guess that the only difference between our decks are the mounts and possibly the guage wheels.

ozzie tractor · Jul 16, 2016

dont use after market washers. the factory washer is designed to let the blade slip at a set torque, giving each blade its own protection clutch set up. a aftermarket washer could cause massive spindle, belt, belt tensioner and deck gearbox failures if it increases the slip torque. in my mind they are cheap at $4 each. a deck box is $1500. those washers are really cheap actually.

victor43 · Jul 20, 2016

Good advice ozzie tractor. Didn't realize that the washers were a torque limiting device. Bit the bullet and ordered from the Kubota dealer @ $6.40 each. Cheap price to pay to save a $1500 gear box. Thanks

SPYDERLK · Jul 20, 2016

ozzie tractor said:
dont use after market washers. the factory washer is designed to let the blade slip at a set torque, giving each blade its own protection clutch set up. a aftermarket washer could cause massive spindle, belt, belt tensioner and deck gearbox failures if it increases the slip torque. in my mind they are cheap at $4 each. a deck box is $1500. those washers are really cheap actually.

No. The washers are crushed flat by much less than the torque of installation. At that point they merely spread the flattened portion of the clamp force over a wider area than would a flat washer. This supports the blade better giving a more sound mechanical joint. Effects on slip torque are present technically, but grossly inaccurate in practice. Any belleville washer of the same dimension and thickness will do as well.