At our Hydrostatic Pump Repair Site, we offer many types of Hydrostatic Transmission Repair and information relating to Hydrostatic Parts
Today we will discuss:

Assembly Procedures for Variable Displacement Pump Series 40 M46 – Part 1

Always clean and oil parts before you assemble the pump. Make sure you torque oil threaded parts to levels that are recommended.

(Part are have their own high tolerance levels to surfaces, prior to assembly. Make sure all openings and ports from contamination).

The servo stop sleeve serves as a maximum displacement stop and is available in different lengths.

When you are reassembling the pump, make sure you put in servo pistons which include bearing and seal rings. Put in the inner spring guide, servo spring, servo stop sleeve and out spring guide onto the centering adjustment screw. Put the plain nut and half nut onto the centering screw. If the unit has a build code 87-14 use a self locking nut, it should be replaced with the plain nut and half nut when repairing.

Hold the centering screw from turning and tighten the plain nut to compress the servo piston spring.

Slide the centering spring assembly into the servo piston. Put in the retaining ring on the piston to retain the spring assembly. If it can’t be installed, compress the spring by tightening the plain nut on the centering screw.

The nut on the centering screw needs to be loosened to seat the retaining ring, then tighten the nut until all axial looseness between the screw and the servo piston is eliminated. If the nut is too tight, the spring assembly will be loose in the servo piston. And if the nut is too loose, the centering screw will be loose in the spring guides.

If you have any questions on the subject, please leave a comment. We will get back with you.

Call 800-361-0068
email: sales@hydrostatic-transmission.com