Bobcat M610 Split Jackshaft Wobble

[Poorskidsteerman]

I have a (unknown year) M610 bobcat with the split Jackshaft. The problem im having is that the shaft has a slight wobble in it. When I bought this machine It did not run. It would sputter because one of the valves was dropped and a hole was in one of the pistons. As long as I've toyed with it there was always alittle wobble in it. It looks like the previous owner tack welded the block in place at one point. Is there a specific way to get the wobble out of the shaft? Ive tried to correct it all weekend.

 

[6brnorma]

The "spot welds" are not a good sign….possibly been an ongoing issue. Worn bearings (2), bent shafts (2), out of tolerance shafts, out of balance driven sheave, worn bushings in the driven sheave (5), block not properly installed (4 bolts point one way and 4 the other, stamped end of blocks aligned) or key not aligned in the keyway in the block. Lots can be wrong…needs to be corrected as it will not get better and will become more costly and even dangerous.

 

[Poorskidsteerman]

The "spot welds" are not a good sign….possibly been an ongoing issue. Worn bearings (2), bent shafts (2), out of tolerance shafts, out of balance driven sheave, worn bushings in the driven sheave (5), block not properly installed (4 bolts point one way and 4 the other, stamped end of blocks aligned) or key not aligned in the keyway in the block. Lots can be wrong…needs to be corrected as it will not get better and will become more costly and even dangerous.

The bolts on the block are configured up/down/Down/Up. Possibly that has something to do with it? The shafts are straight I took the block off and it was sitting correctly on the keyway

 

[6brnorma]

The bolts on the block are configured up/down/Down/Up. Possibly that has something to do with it? The shafts are straight I took the block off and it was sitting correctly on the keyway

Use a small mirror to look down towards the three pins in the driven sheave and insure that the bushings are in good shape (not oval shaped). The next most likely concern would be the two bearings on the shaft. Do you know how much 'run out' you have on the shaft at a high RPM?

 

[Poorskidsteerman]

Use a small mirror to look down towards the three pins in the driven sheave and insure that the bushings are in good shape (not oval shaped). The next most likely concern would be the two bearings on the shaft. Do you know how much 'run out' you have on the shaft at a high RPM?

I checked runout and I have more next to the block amd minimal at the ends where it goes into the chain boxes. The Sheave looks pretty good.

 

[6brnorma]

I checked runout and I have more next to the block amd minimal at the ends where it goes into the chain boxes. The Sheave looks pretty good.

Without knowing what actual numbers are…..I'm not sure what "more next to the block and minimal at the ends" really is…..maybe you don't have much of a problem….maybe you do…but without seeing it or knowing what actual runout is, I'd just watch it close.

 

[Poorskidsteerman]

Without knowing what actual numbers are…..I'm not sure what "more next to the block and minimal at the ends" really is…..maybe you don't have much of a problem….maybe you do…but without seeing it or knowing what actual runout is, I'd just watch it close.

https://youtu.be/Ws-xEonAyjM