JA00045
PARTS-SERVICE
September 10, 1997
Class I and II Product
GRAM
SUBJECT: Main Hydraulic Pump Coupling, P/N 355329 or 1453260
It has been discovered that information in the service manual regarding the installation of this hydraulic pump
and motor coupling is incomplete. There should be a clearance of 16+ 0.5/ - 0 mm (0.630+ 0.020/ - 0.000 in.)
between the flat inside faces of the coupling (see below drawing). Any time the hydraulic motor and pump are
separated, the clearance in the coupling must be checked.
Below is the correct procedure for installing the coupling:
1. Install one half of the coupling on the motor shaft and the other half on the pump shaft. Do not tighten the
set screws at this time. Note: the coupling halves should fit easily on the shafts. Do Not Hammer the
Coupling On. If the coupling is too tight on the shaft, replace it.
2. Insert the cushion material in one half of the coupling and assemble the motor and pump. Make sure that
the halves of the coupling are properly engaged. Also be sure to maintain the correct orientation between
motor and pump. Torque the pump mounting bolts.
3. Adjust the position of the coupling halves to achieve the required 16 mm (0.630 in.) clearance. The small
points on the flexible element should just be touching the coupling halves at this point. Then tighten the set
screws.
16 mm (0.630 in.)
small point on
flexible element
flexible element
We reserve the right to make changes in design or add improvements without incur-
ring the obligation to make such changes in equipment previously manufactured.