150 mariner runs rough at low speed or idle

[edeuka]

spits and spules running under 1000rpm makes it in possable to dock boat at public landing runs good above say 1500 rpms i have installed water seperator spark plugs inline gas filter there is little air bubbles in see thru inline filter should i rebuild fuel pump any sugestion are welcome this boat is dry docked and delaware flounder are safe untill i can fix this problem

 

[AndyL]

Re: 150 mariner runs rough at low speed or idle

What age is the engine?? You will have to eliminate all the obvious servicable parts eg fuel line (check for air leaks), does pumping the fuel bulb have any effect. If the fuel pump is more than 2 years old then replace the unit as a kit.Renew spark plugs if they are more than a few years old. Run a compression test and see what if any cylinders down on compression. Check that all the throttle linkages and attached advance linkages are connected and operating correctly.<br />If all that Ok the problem may be deeper. Go for the simple stuff first and eliminate progressively what is causing the condition.