fuel problem 91' johnson 150 (VRO)

[kstesch10101]

i prime the fuel system using the squeeze ball. It fills the carbs up just fine and the engine runs for about a minute until the carb bowls run dry. I've replaced the fuel/VRO pump ($250) because the diaphragm was old and dry rotted. The diaphragm in the vacuum switch ($100) too was dry rotted. So i replaced that. Still the same thing happens, runs for a minute, and dies.... I’ve checked for a possible air leak in the fuel system... none to be found... I'm stumped... please help.

 

[tpggolf4]

Re: fuel problem 91' johnson 150 (VRO)

check the primer bulb. Sounds like the check valve has gone bad in the bulb. Does the bulb go soft after engine starts, or has died?

 

[seahorse5]

Re: fuel problem 91' johnson 150 (VRO)

Check the intake manifold gaskets, if they are the original black ones, they are probably swollen and distorted from the chemicals in today's gasoline. The replacement gaskets are brown and resistant to todays fuels. Also it would be a good idea to put carb kits in that old a motor as the new parts are also fuel resistant.