I have a 71 Evinrude, 60hp, Model 60173E which has a 'cylinder plug'(Part #307544) located on top of the cylinder next to the thermostat housing. It is a threaded bolt with a slotted head. What purpose does it serve?
My guess it's just a plug to cover a hole made during machining of the block , drilling a water passage ?<br /><br />If it's not leaking just leave it i place .
Don't know what that plug on my 70 115 was there for... but it isn't there anymore.. I replaced it with a 1/8 barbed fitting and some tubing and made me a pisser. Didn't like not having one. Works great.
