May 5, 1959
SERVICE BULLETIN NO. SB-717
Subject: PINION THRUST BEARING AND SHIM ASSEMBLY - 50 HP GEARCASE
Pictured are two pinion thrust bearing
and shim assemblies, used in the 50 H.P.
engine gearcase. A recent change in the
50 H.P. gearcase incorporates the use of
the larger thrust bearing part number
377658, which is 25/64 inch larger in
o.d. than bearing 377138 previously used.
The new larger bearing and shim assembly
part number 377658 is presently being
used on production of the model V4-V4S-11B,
and in the following service gearcase
assemblies.
377699 Gearcase and bearing assembly
Supersedes 377242
377705 Gearcase complete - supersedes 377482
378076 Gearcase Complete - Long shaft
supersedes 377742
When servicing the pinion thrust bearing on the 50 H.P. engines prior to model V4-V4S-11B,
it will be necessary to properly identify the parts required, should the gearcase have
been replaced previously with one of the superseding assemblies.
The easiest way to determine which thrust bearing and shim assembly is required, is to
measure the old bearing. If the old bearing O.D. measures 2 3/64 inches, assm. 377138
is required. If the old bearing O.D. measures 2 7/16 inches, assembly 377658 is
required.
IMPORTANT. Make a notation of this change in your parts catalogs, so that there will
be no error in ordering replacement bearings.
JOHNSON MOTORS
Jack Penland
Jack Penland
Service Department
JP/eb