Merc 7.5 won't pull fuel from tank

erichy

Seaman
Joined
Apr 3, 2010
Messages
57
Hi guys I'm a newbie to boats and have a question about my kicker motor. I put a 7.5 Merc on my Wellcraft 196 and it won't pull fuel from the tank if the fuel line comes from above the fuel hookup.When in the water and the tank is in the boat the line goes over the transom and to the motor, the tank is about even with the fuel hookup. It won't pressurize the ball when its in the boat. When I'm in the driveway and the tank is on the ground below the motor there's no problem, it pressurizes the ball and runs fine. The tank is a plastic Walmart cheapie that was given to me and the line and ball are brand new. Is it the tank or does the line need to be below the hookup to work? I figured it's a pressurized system so it wouldn't matter but like I said I'm a rookie.
 

CharlieB

Vice Admiral
Joined
Apr 10, 2007
Messages
5,617
Re: Merc 7.5 won't pull fuel from tank

I suspect the check valves in the primer bulb to be at fault.

When the tank is on the ground the primer bulb is facing upward, the check valves fall closed and work fine.

In your boat the primer is horizontal or sloping downhill, and the check valves fail to close properly.

Try tilting the primer upwards as you primer the motor.
 

erichy

Seaman
Joined
Apr 3, 2010
Messages
57
Re: Merc 7.5 won't pull fuel from tank

Thanks Charlie I hope that's it, I love the free fixes.
 
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