Johnson Service Bulletin SB-870 - Prevention of Piston Sticking

October 17, 1961. Johnson recommended a molybdenum-disulfide-containing Marinecare fogging oil treatment for specified new, replacement, and overhauled powerheads on 40 and 75 H.P. outboards. The original factory instructions and cautions are reproduced below for historical reference.

Johnson Motors Service Bulletin letterhead
October 17, 1961
Bulletin No. SB-870 Powerheads
SUBJECT: Prevention of piston sticking by using Marinecare Rust Preventative (fogging) Oil containing Molybdenum Disulfide.
A solution has been found, in response to field reports, to the problem of piston sticking on 40 and 75 h.p. engines. This solution lies in the use of a product called "Marinecare Rust Preventative (fogging) Oil CONTAINING MOLYBDENUM DISULFIDE", an excellent antifriction compound. The factory has extensively tested this product in new engines with outstanding results.
Because of the very efficient antifriction qualities of this product, its use is highly effective in preventing piston sticking when properly applied. We recommend that all (1) new engines, (2) powerhead replacements (3) powerheads overhauled with new pistons (whether rebored or not), be treated in accordance with the following instructions prior to delivery to the customer:
INSTRUCTIONS FOR USING RSA'S RUST INHIBITOR CONTAINING MOLYBDENUM DISULFIDE, (SHAKE THOROUGHLY BEFORE EACH APPLICATION).
1. Fog each engine by applying 5 cc's (3/4 ounce) of mixture into each carburetor air intake (2 intakes per V-4 engine) immediately after starting. a. Run engine at a fast idle (about 1/4 throttle) while fogging to insure distribution of mixture throughout the powerhead.
2. At end of run, or tank test, repeat fogging operation with another 5cc's (3/4 ounce) of mixture into each carburetor air intake. a. Apply rapidly with engine running at half throttle and stop engine immediately so mixture will not go through engine and out the exhaust.
CAUTION! Do not use molybdenum disulfide in any form or mixture as an assembly lub- ricant on (1) threads of screws, studs, nuts and bolts, (2) tapers of flywheel hubs and crankshafts, nor any other points or areas which are dependent upon friction for holding power. USE IT AS RECOMMENDED IN THE AFORESAID INSTRUCTIONS ONLY AFTER ASSEMBLY IN THE NORMAL MANNER.
"Marinecare Rust Preventative (fogging) Oil WITH MOLYBDENUM DISULFIDE" is a product sold by RSA Products Company, Detroit, Michigan and Whittier, California. They have made it available through your Parts Distributor in one (1) pint, MC-5 containers.
Because of the above product's effectiveness in preventing piston sticking, we urge that all Dealers order a supply as soon as possible to alleviate this problem. When ordering this fogging oil, be certain to specify "WITH MOLYBDENUM DISULFIDE". Fogging oil is available with and without this compound.
Order only from your Parts Distributor. Do not order from Outboard Marine Corporation Parts Depot, nor from Johnson Motors.
JOHNSON MOTORS
W. W. DeWees Service Department
WWD:eb
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