I am trying to rebuild a carb on my 25hp Johnson model number 25r75 b .My question is , how do you get the little caps or covers off to replace the O rings? There is 3 of them, one large and 2 small ones. Also, on the knob that says richer or slower, Where would be a good place to start as far as settings and also where to run it? Thanks Camofry[/QUOTE
I think you speaking of the core plugs? You carefully drill or punch a hole in it and stick a punch in the hole and rock it out. "Carefully" in that if you go too deep you can cause irrepairable damage to the carburetor body.
I know I will catch heck for saying it, but unless you have good reason to suspect a problem under them, leave them alone. There are no o-rings in there, only fuel passages. True, the passages under the big plug can get plugged by debris and cause lousy idle, but it doesn't happen as often as people think. I have repaired thousands of carburetors and have never yet removed the smaller plugs.
Begin with the idle needle backed out 1 1/2 turns from lightly seated.
I'm surprised you didn't ask about how to remove the bearing (seal) for the idle needle. Have you figured that out yet?
