Joe McCauley – FYI Tech Tip on Breaking in a Racing Motor

Here’s a motor that fits well with my April 2013 Antique Outboarder technical article on the Johnson Classic 1971-2001 2 cyl. looper. This is a 1985 short-shaft 45 hp work motor (or commercial model) with a tiller handle and rope-start. Although it’s short-shaft the gearcase is the fat, low geared one. I bought the motor for $250 and it runs.

It can be used for fishing and playing or for my purposes while breaking in SST45 racing power heads.  All 2 cyl. looper power heads 40, 45, 48, 50, 55, 60 hp are the same excepting cosmetic differences, one is easily convertible to another.

So I can unbolt this powerhead and bolt on a rebuilt 60 hp SST45 powerhead for break-in. Breaking in a racing motor is tedious.  It takes four hours at idle or low speed with a thermostat which is necessary in order to make the motor run hotter during break-in. Then we remove the thermostat and let it rip. I will make a wiring harness to use a 12 lb 640 amp racing battery to electric start the racing powerheads for break in, as those motors generate 160-190 psi compression.  Joe Mcauley

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