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Mark Denison

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My 620 PTO needs help!



I bought my 620 new in Nov. 1974. I used to do a limited amount of custom garden plowing/tilling for fellow Church members, friends, & neighbors. I also mowed 2-3 acres for the 1st 25 years until the mower deck was too rusty to continue. I repowered it in 1999 with a 22 HP Kohler Command, before there were repower kits to my knowledge.

Almost two years ago, after extensive use of the Simplicity 48" tiller, apparently one of the bearings seized so suddenly (after I switched the rear PTO off), that when I tried to switch it back on again a few minutes later, it instantly killed the engine "graveyard dead".

Can I replace the short (rear) shaft, it's two bearings & whatever else is necessary, just by removing the seat, top cover, & transaxle cover? Is it likely that I'll have to also replace the long shaft & it's gears & bearings?

I may have availability for used parts nearby. I haven't called Sandy Lake yet.

Thanks for whatever advice anyone can offer.


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I think you will do better posting your question in the "Talking Tractors" forum, which will be more widely read. I'm sorry that I can't help you with your specific problem. Welcome to the site.


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Posted (edited)

The hub on the front of the shaft that connects to the magnetic clutch, the mfg used gap filler on the spline end of the shaft.

Also the bolt that secures the hub onto the shaft has used lock tight, Once the hub has been removed you'll find a spacer, behind the spacer an o-ring.

The spacer is machined at one end for the o-ring make sure you reassemble in the same order these parts came off.

Hub removed, next an oil seal can not remember if they used a snap ring in front of the bearing.

I used a peice of wood jammed between the rear inside PTO gears to loosen the hub nut.

After the front bearing has been removed slide the short shaft forward, then lift upwards then draw it back out through the rear of the transmission.

The front bearing is a roller while the rear bearing uses a needle bearing.

If you have to remove the centre idler gear or the bottom PTO gear, be prepared to learn some patience.

Reinstalling those bottom gears along with the thin spacers is a bit tricky, for the bottom gear I used heavy grease to hold the shim in place, then cradled the gear using fishing line to lower the gear into place.


Edited by SimpleOrange
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