Thread: 1985 235 evinrude rough running

If it's not pumping up you could have #1 air leak in fuel line, is it original? #2 Ethinol could be breaking down inside of fuel line causing a blockage, #3 could have a bad check valve in bulb letting fuel leak back when you release pressure on bulb. If you have a vented cap on fuel tank make sure it is open and you don't have any kinks in fuel line.

You could have some trash floating around in a fuel bowl. Like Cray said check all your fuel lines. They should be soft and pliable. When they get older and hard they can crack letting air in. Since you found a loose screw on a carb it sounds like someone may have been working on them. Check all the screws especially the mounting bolts.

when you pump the primer bulb hold it in an upright position, sometimes the check valves won't work as well in a horizontal position, and see if that will let it get hard. Works for me on my old Johnny 85HP

i think fuel does leak back on this Bulb would it have like a miss and not run as it should ? it doesn't run out of gas even WOT is what has me confused ..
I have had carbs off tighten bolts and made sure they were clean . also changed fuel line on the motor .. i am gonna try a new line and bulb see if that helps ..
i will also try to turn it upright

If none of that works the next time you take it out and it starts to act up pump the primer bulb. If it acts like it wants to go rebuild the fuel pump. Its a pretty easy job and a kit cost about 20 bucks.

Did you change the bulb on your boat .. I tried what you said and it gets hard .. i can feel gas going right back out of the check valve when its flat ..I just dont see how its a gas problem but i really hope its this simple lol ...need to hear some stories of people having trouble with the Primer bulb i guess ,,,

Originally Posted by wannabe fisherman

when you pump the primer bulb hold it in an upright position, sometimes the check valves won't work as well in a horizontal position, and see if that will let it get hard. Works for me on my old Johnny 85HP

Yep. Went through 3 primer bulbs in two years. Bought a mercury OEM primer bulb and now problems to date. One of the previous bulbs leaked down one had a slight leak around one of the crimped ends.

Meant "no" problems to date