piper184
Gold Member
Does your tractor look like the picture in post #29 just above your post?
If so, the differential lock works by the cam on the lever pushing the rounded bolt/shaft inwards. This shaft has a fork attached to it that slides the jaws together which locks the axles. The shaft has a spring on it which pushes it back outward and unlocks the axles.
The lever has a cam built into it that forces the shaft inward as the lever is pushed down. The rounded button (bolt) is threaded into the end of the shaft and is used to adjust the length of the shaft so it contacts the cam properly. The jam nut is there to lock the bolt once it is adjusted.
You can see a parts diagram here: Drive Gearbox - 18-28HP Tractors
Note that there are images on this page and the one with the diff lock is the one on the right hand side. Also if you hover your mouse over the image it will show a zoomed in version that your can scroll around to get a closer look.
Part number 131 in the middle of the picture is the fork that slides the claw. As you can see it is connected to the rest of the assembly shown just below it.
Part number 139 is made of cast iron and has the cam molded into it.
Part #138 is the bracket that bolts to the gearbox.
If you scroll down the parts list on the right until you get to #138, click on the part number and it will open a picture of that part.
It appear that Jinma used a couple of different designs of how the lever was attached to the tractor. If you could post a picture of the outside (button end) of the shaft where the lever was removed it would help identify your setup.
In any case, you could probably fabricate something that would bolt to the two tapped holes in the gearbox housing then make a pivot so that it pushed the button inward when you wanted to activate the diff lock.
If so, the differential lock works by the cam on the lever pushing the rounded bolt/shaft inwards. This shaft has a fork attached to it that slides the jaws together which locks the axles. The shaft has a spring on it which pushes it back outward and unlocks the axles.
The lever has a cam built into it that forces the shaft inward as the lever is pushed down. The rounded button (bolt) is threaded into the end of the shaft and is used to adjust the length of the shaft so it contacts the cam properly. The jam nut is there to lock the bolt once it is adjusted.
You can see a parts diagram here: Drive Gearbox - 18-28HP Tractors
Note that there are images on this page and the one with the diff lock is the one on the right hand side. Also if you hover your mouse over the image it will show a zoomed in version that your can scroll around to get a closer look.
Part number 131 in the middle of the picture is the fork that slides the claw. As you can see it is connected to the rest of the assembly shown just below it.
Part number 139 is made of cast iron and has the cam molded into it.
Part #138 is the bracket that bolts to the gearbox.
If you scroll down the parts list on the right until you get to #138, click on the part number and it will open a picture of that part.
It appear that Jinma used a couple of different designs of how the lever was attached to the tractor. If you could post a picture of the outside (button end) of the shaft where the lever was removed it would help identify your setup.
In any case, you could probably fabricate something that would bolt to the two tapped holes in the gearbox housing then make a pivot so that it pushed the button inward when you wanted to activate the diff lock.
