Johnson Service Bulletin SB-859 - Cotter Pin Change

Issued August 10, 1961, this bulletin describes the revised cotter pin used on V-75 propeller nuts. Both old and new versions carry part number 307244, but Johnson specified the larger new pin for V-75 engines to reduce movement and breakage.

Johnson Motors Service Bulletin letterheadFactory comparison of old 1/8-inch and new 9/64-inch cotter pins, both marked 307244
August 10, 1961
Bulletin No. SB-859 Propellers
SUBJECT: Cotter pin change - propeller nut; 75 h.p. V4S-12 thru V4AL-13F.
Illustrated are the old and new cotter pins for the V-75 propeller nuts. While both pins carry the same part number, 307244, note that the overall length of the new pin is slightly longer than the old one, and also has a bigger diameter. This new, larger pin is the only cotter pin that should be used on V-75 engines.
The larger diameter is the more important difference since it reduces wobble of the propeller nut formerly experienced with the old cotter pin, and in turn reduces cotter pin breakage.
new style cotter pin is available from the parts distributors at the same old list price of $.10 which is subject to the usual standard parts discount.
This change does not affect dealers' stocks of the old style 307244 pin because they can be used in other applications where a 1/8-inch diameter pin of the same length, or shorter, is required. As one example, they can be cut to the length required for use on RD propeller nuts.
JOHNSON MOTORS
W. W. DeWees Service Department
WWD:eb
NOTE: Post on your V-75 index.

Related part reference

307244 - Cotter pin, revised larger-diameter version for V-75 propeller nuts. The original bulletin states the new pin retained the existing part number and ten-cent list price.