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I need to remove the flange from the driveshaft on an R51/3. I've tried to remove it on a small hydraulic press without luck. I have access to a larger one, but I'm not sure this is the correct procedure. Any help would be greatly appreciated.

Hi Scott,

I haven't done this myself, but I have been advised that the interference fit between the shaft and flange requires about 10 tons of force.

The load should be applied to the center of the shaft, not the outer hollow portion, and the flange should be well supported at the shoulder around the shaft. Failure to do both will quickly trash the shaft and flange.

I have two shafts that I need to press apart and I am getting close to welding up a rig out of a big jack.

Also, mark the shaft so that that the flange can be put back to the same place.

Good luck,

Bruce

Bruce is quite right Scott, this is not something to be attempted in the home workshop. I have refurbished many plunger-frame shafts and had a support collar made up by a local engineering company who then quickly and cleanly parted the shaft and flange with a large hydraulic press. But BE WARNED...

If you send away the shaft for plating, do ANYTHING to prevent the mating surfaces being buffed or re-plated! The shaft and flange fit should be TIGHT on reassembly! Also measure the exact distance from the end of the shaft to the flange to ensure it is pressed back to the spot. This will determine the running gap between the flange and rubber coupling.