Hi, on an '84 v-6 150. I checked the check valves by blowing through them, and they all worked but the one on the airbox. It would blow both ways but real hard to blow. Is that a check valve or just a fitting with an orifice? thanks
The attached pic is for my 1996 150HP Mercury outboard. It shows which ends of the bleed lines have a check valve and which ends have only a pass-thru fitting. I don't know for sure that the bleed line design didn't change since 1984 and you did not provide a serial number for me to check, but this pic may be helpful to you anyways.
A better way to get reliable information for your particular model year is to go to a website with parts lists and diagrams. Mercury Parts Express or Doug Russel Parts are two good websites for such info.
