1972 Johnson 50hp Electric shift throttle problem

I got this motor in a trade, and put it on my bass boat. Guy I got it from worked at a marina and put new carb kits and new impeller in it. Then it sat for 2 yrs. The impeller is fine, still soft and like new. I cleaned the carbs and they look like new. Motor runs great on the top end out on the lake, but will not idle. I set the idle a little fast on muffs, but with the back pressure in the water it won't idle. To "idle" I have to leave it slightly in forward gear. I have an original 1972 OMC manual but it doesnt say how to adjust the throttle cable. It is close to idling in the water with the trunion adjusted all the way forward, which I assume is not good, but it still dies. I've tried adjusting it inside the control box and also at the motor. I can't get it right but am so close its driving me crazy. I can take some pics tonight if it helps. Thanks in advance, Randy.

Re: 1972 Johnson 50hp Electric shift throttle problem

Disconnect the throttle cable and adjust the motor so it will idle in the water, in gear, with the throttle lever against the idle speed screw.

Now, install the control cables to fit the motor. Don't re-adjust the motor to fit the cables.

Re: 1972 Johnson 50hp Electric shift throttle problem

Ok I'll try that tonight. I'm suspecting that since he worked at a marina, he just used a throttle cable they had laying around. On the throttle wire that goes inside the plastic piece inside the control box, it has several indentions where the allen head screw tightens down. To get the cable the right length at the motor, I need about another inch in length of threads at the trunion, which is what is leading me to believe this is the wrong cable.