Thread: '91 Evinrude 40 fuel delivery problem

Hi, new member here. Would like some help with a with a fuel delivery problem. I have a '91 Evinrude 40 with a VRO2 pump (oil inject disabled) that has been giving me problems. The engine runs well (5600rpm at full throttle) until the level in the onboard 12 gal. fuel tank drops below 2/3 full. The engine then starts to sputter and surge like it's sucking air, and the primer bulb gets soft. Re-priming the bulb gets it back going for a few minutes, and then it starts cutting out again. I have replaced the fuel hose/primer bulb, the fuel lines from the manifold to the carbs, and finally, after realizing that fuel level in the tank was an issue, the withdrawal tube in the tank, and the problem still persists. I think I have eliminated every possible issue except a weak fuel pump. Am I on the right track here? If so, can I get a non-VRO fuel pump to replace it with? Thanks- M

Originally Posted by Mountain Fork

Thanks for the reply. If there was a venting problem with the tank, wouldn't that prevent fuel from being picked up even when the tank is full? The fact that it is lifting fuel from the top four inches of tank without problems is what is throwing me here.

Normally when a vent gets plugged the primer bulb will collapse after a while