Johnson 1967 60HP Low Running Speed problems

[RickyAust]

I took my boat out for the first time this season last saturday after getting it serviced by my local service guy (ie tune up and new plugs) 2 weeks ago. The motor starts fine, however ever since owning the motor (just on 12mths now) I have only been able to keep it running in idle and at low speed with the choke. If I stop using the choke it stalls. It runs fine at high speeds but its when I am coming back into the jetty and have to really idle along at a slow speed that I have problems. Even after running the motor for sometime it still stalls at low speed.

I tested it again tonight and noticed that if I use the primer bulb it actually keeps the motor running. Could this be a fuel pump issue? or even the carby low speed adjustment levers need playing with?

Any advise would be helpful as apart from this low speed running problem the motor runs perfect.

 

[F_R]

Re: Johnson 1967 60HP Low Running Speed problems

Either/or. Can be either one or both. One thing for sure, it is starving for gas. The fuel pump supplies it, the slow speed needles/levers determine how much of it it gets.

Can also be a leak in the fuel lines between the fuel pump and gas tank, sucking air.

 

[RickyAust]

Re: Johnson 1967 60HP Low Running Speed problems

I will replace all my lines just to be sure. I do recall a while back first hose inside the motor that delivers the fuel was split so I shortened it. Maybe that is leaking air.

In terms of the Fuel pump, can you take them off and give them a clean or should I replace it? I replaced the filter and gasket end of last season.

In relation to the needles/levers, do I adjust both and moving them which way delivers more fuel? clockwise?

 

[tashasdaddy]

Re: Johnson 1967 60HP Low Running Speed problems

i would say the pump is ok, as it keeps up with high speeed. could be clogged low speed jets, if adjusting the needles doesn't help then we will go into the clogged jet. remove the knobs, to adjust, as the knobs have stops on them.

here's the best post i know about the carb. http://forums.iboats.com/showthread.php?t=167352

 

[RickyAust]

Re: Johnson 1967 60HP Low Running Speed problems

I am going to attempt to adjust the levers/needles tomorrow. I know I should adjust one at a time, and wait about 20secs after each adjustment. Facing the motor from inside the boat, should I move both levers inwards or both clockwise?

 

[F_R]

Re: Johnson 1967 60HP Low Running Speed problems

Clockwise = leaner
Counter-clockwise = richer

It shouldn't take much unless somebody has already been messing with them and got them way off. That's why the stops are there.