old johnson carb problem

[cconger]

hi,<br />I have a 1967 johnson super seahorse 40hp. I have recently got it running. I have two problems i need help with. <br />1. It runs fine at low rpm. I took it out and as soon as you hit the throttle, the engine speed will increase slightly then the engine will decrease back down to idle without moving the throttle back down but wont quit. I have rebuilt the carb but have not tried to see if it is fixed. <br />2. Also when you first shut off the engine, gas comes out of a hole on the side of the bowl on the carb. The hole is stock, but there might be a plug missing, iam not sure. The carb is a fixed high speed jet model. I have rebuilt the carb and it still does it. Iam wondering if there is supposed to be a plug in the whole. When looking at the carb on the engine the hole is on the right side of the bowl.<br />Any help would be great.

 

[Paul Moir]

Re: old johnson carb problem

Do you mean the plug down at the bottom of the bowl, on the right side, sort of in the 'sump'?<br />That ought to have a plug in it, and you would run very lean as you throttle up if it wasn't in place. Since the idle circuit works independantly of it, it wouldn't be as affected.<br /><br />Hope this helps!