1987 Toro Mower Model #20620 Pivot Arm #49-7720 Problem.

[Rich Speers]

Hey Everybody,

Very strange problem. When I put it in drive and start mowing the pivot arms on rear wheels start rotating backwards instead of being stable so the deck on the back wheels lowers and I can't cut. I removed one and it looks fine. I did grease the zerks and thought maybe too much grease caused the pivot arms to slip but that's not the case. Do these wear out? Is there a cheap way to repair them? I've asked around but nobody has the answer. Hate to spend big bucks replacing both pivot arms on this old mower.
Thanks

 

[Rivets]

Sounds like privet spring has lost its tension, common as the unit ages. Two things you need to check. One, are the pivot arm assemblies being held tight against the mower deck. They are held in place by an E-clip and I have found that as the unit ages the groove that the clip goes into wears,no longer allowing the clip to hold it tight. Second, are the slots which the spring arm pins it’s in worn, allowing the arm to jump out easily. Take a look at this service manual and post back with your findings. https://www.toro.com/getpub/25572

 

[Rich Speers]

Sounds like privet spring has lost its tension, common as the unit ages. Two things you need to check. One, are the pivot arm assemblies being held tight against the mower deck. They are held in place by an E-clip and I have found that as the unit ages the groove that the clip goes into wears,no longer allowing the clip to hold it tight. Second, are the slots which the spring arm pins it’s in worn, allowing the arm to jump out easily. Take a look at this service manual and post back with your findings. https://www.toro.com/getpub/25572

Thank you!!! Much appreciated!