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JD JS63 Transmission engagement

2469 Views 4 Replies 3 Participants Last post by  tommiy
I inherited an old JD JS63 walk behind mower. It had not been started in a decade so I stripped down the carby and fuel system and replaced the fuel tank. It now starts like an absolute champion on first pull. It had had very little mileage so its not surprising.

My issue is that the engagement of the transmission is very poor. It appears that the lever on the transmission should be internally spring loaded and that it should put itself essential into netural when the handle bar engagement is released. Unfortunately mine seems like the internal spring is had it? If I engage and then release it may pull back but some times very very slowly and sometimes not at all. It moves so little that the cable bunches up. When its engaged the mower propels with no issues and the 3 speed works fine.

I was looking for a service manual or what appears to be the technical manual to find out the details on the transmission and if it is possible to service. However it appears impossible to find one of these. I've searched this forum but not found anything relating to this style of issue. Does any one have experience with these transmissions that can assist? Is it possible that sitting for a decade the internals have essentially become clogged up? Can the transmission be pulled down and repacked as such?

Any help appreciated.

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that is very similar to the trans that the 14sb uses I can see that it uses a much larger spring to return the lever than the 14sb. I would start by disconnecting the cable from the lever and manually move the lever to see if it returns more quickly. if not then you will need to open the trans and clean out the old grease and re-lube everything. if it does return quickly then the cable will need replaced. The 14sb the trans tilts up when the engagement lever is pulled and when the level is released the trans tips down helping to disengage the lever so it uses a much smaller spring. In your video it appears the trans is fixed in place and uses the larger spring to pull the lever back to its neutral position. I found a manual on line for the 14sb that covers all the transmissions that might help you pm me and ill send the link to you its a very large file and has no hyper links do you have to page through it until you find the transmission section but it might help you with disassembly. you can also look up my trans rebuild that I posted on here they are quite in depth but are on the 5spd the 3 speed from what I can tell uses as pacer on the shaft in place of 2 of the gears
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I agree -try a new cable first. mine was slow to disengage and a new cable fixed it. befor I changed the cable-I added a spring to help the engagement lever move better. this helped for a long time but the new cable was the real fix
Without the cable connected, and assuming that the far left is the return position it only moves about 1/3rd of the way. I'll upload a video when i get the opporunity. Thanks for the feedback.
Just realised I had not responded here (yes 3 years). I repacked the transmission/gearbox with new grease. 3 years later its is still going strong!!
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