I’ve had motors where the plate with the intake screen is on backwards so the screen is not in the same position – I haven’t seen this affect cooling, probably because the screen isn’t too far off center; but on late 1950s/early 1960s 10 HP motors that have aimed, directional, ported holes on that plate, I got a motor that had the plate on backwards so the ports were aimed the wrong way. I caught the problem before putting it on a boat, but I think it would have cooled at an idle, but maybe not so well at WOT.
My super quiet 40 hp motors have a row of 5 or 6 holes at one end of that plate instead of a screen. On one of these someone has drilled more holes (slightly bigger too) so the row goes almost all the way across. The motor cools fine but I’m wondering why they drilled more holes?
Oh – and Crosbyman – thx for posting that cutaway diagram!
Dave
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