TM 9-4940-444-14 & P
CHANGING HAND OF ASSEMBLY
The worm gear set and reducer will operate equally well in either direction and changing to the opposite side gear shaft
extension is a simple operation.
To reverse the gear shaft extension, it is necessary to remove the gear caps and proceed as follows: Press one bearing
and the gear off the shaft. Reverse the gear on the shaft and reassemble bearing. (Note: On 73500C, a spacer is used
between the gear and the bearings.) After removing the caps, look for the stamping on the housing flange face against
which the shims are placed, such as +2. This indicates the amount(O.002") which the housing flange is off from being
central. Housing may be plus or minus.
If this is not more than plus or minus 0.003", the gear assembly may be reversed leaving the original shims on the caps.
If, in exceptional cases, the total difference in flanges are off more than 0.003", take the necessary amount of shims from
the cap on the shortest side and leave them on the housing so as to centralize the housing flanges. For instance if one
side is -2 and the other +3 leave a 0.005" shim on the -2 flange side of the housing. Then reassemble gear shaft and
bearings in housing. The shims determine the positioning of the gear set and also provide required bearing running
clearances. Damaged shims may develop oil leaks. Replaced shims must be same thickness as original shims. This
procedure is to maintain the original alinement the gear with the housing flanges. A similar procedure is followed if it is
desired to reverse the worm shaft extension. (NOTE: If the worm shaft is reversed, the gear must also be reversed.)