OMC 5.0L STARTS THEN DIES WON'T STAY RUNNING

[cottageboy]

Hello all, I'm new to this forum and looking for help.
I have a1993 OMC 5.0L 302. On cold start I pump it six times and turn it over. The engine will start then immediately die. It will only start if I prime it. It seems like it isn't getting any fuel. It ran great that last time I was at the cottage 2 weeks ago. I'm thinking it's the fuel pump.
I seem to remember droplets of moisture (fuel I'm assuming) in the orange transparent tube going up to the carb. The OMC service manual says if there is any fuel in that line then the diaphragm has ruptured and the fuel pump needs to be replaced. Not sure if droplets justify a rupture or not.
The fuel filter was changed a few years ago. This boat does not get used much at all. I have a hard time burning a full tank of gas in a summer. But love it and just couldn't part with it. It's barn stored so it's in great shape for it's age. I really don't think it's the fuel filter as the filter has only seen about 70 gallons of fuel in its life time. I live in Michigan and winterize it by filling the fuel tank and adding STA-BIL. This procedure has served me well for the past 24 years.
The pump is not cheap $245.00 so I don't want to replace a good pump but I don't have the gauges to measure vacuum or fuel pressure on this pump.
I'd appreciate your thoughts on the cause of this starting issue.

Thank you
Cottageboy

 

[savetexomabeaches]

whats the id on the fuel pump flange

 

[Scott Danforth]

you should only need two pumps, then press the throttle only button, and move the throttle to about 1/4. then start the motor. once it fires, back off to about 1500 RPM for a few minutes, then return to idle.

 

[alldodge]

Its normal for a boat sitting for some time to have the gas in the carb evaporate, so the bowl would be dry. Need to cranks the motor over 10 to 15 seconds, then pump the throttle and try again.

To find out if its the pump is the issue, put a fuel pressure gauge inline between the pump and carb. Pressure should be between 4-7 psi, and motor needs to be running steady to get a reading

 

[cottageboy]

Update: Long story short. Not the fuel pump but the safety kill switch not pushed on all the way.
Why would they wire a boat this way? lf safety switch is not engaged then the boat should not even turn over let alone start then die.
Remember: check the simple things first.
Tried to attach a picture but this site won't let me.

Cottageboy.

 

[alldodge]

Glad you found it, but the kill switch turns off power to the ignition (things like coil and ECM). It should not fine but will turn over. Guess your switch was intermittent at making just a slight contact every once in a while