'70 4hp Johnson stalling..

[outdoorsman10]

Had boat on the water today and it repeatedly stalled but never did his when I test ran it in a rain barrel a few weeks ago. It has fresh fuel (50:1) and line seems fine. Am I looking at a pump problem? Motor surges back to life when I squeeze primer bulb.

 

[Rick.]

Re: '70 4hp Johnson stalling..

It sounds as though your fuel pump may be getting weak. Have you checked the fuel pump filter screen and are you certain your gas tank is vented? I had the same stalling problem with my 71 4 HP Evinrude and I cleaned and rebuilt the carb. and it has worked ever since. Best of luck. Rick.

 

[outdoorsman10]

Re: '70 4hp Johnson stalling..

Never thought of that.. Any idea why it would also stall when trying to adjust carb at high idle or would the filter cause this as well?

 

[Rick.]

Re: '70 4hp Johnson stalling..

If the filter is plugged up it would. Do you mean High Idle or High Speed? Rick.

 

[outdoorsman10]

Re: '70 4hp Johnson stalling..

High speed.
Filter is clean as a whistle. Would the pump be a scavange system or somewhat mechanical?

 

[Rick.]

Re: '70 4hp Johnson stalling..

High speed.
Filter is clean as a whistle. Would the pump be a scavange system or somewhat mechanical?

I'm not sure what that means (scavange system or somewhat mechanical). Try to elevate your fuel tank above the engine and see if it works better. If it does that would mean it's the pump. I am assuming yours has an external tank. Your tank is vented? Rick.