2000 mercury 240 EFI won’t start

[matthewdandrea]

I have a mercury 240 EFI that I’ve been having an issue with. I was messing around trying to remove the throttle guardian, but when I go to start it up, cranks and cranks and cranks but won’t start up. I thought it was possibly something to do with the lanyard stop system but I checked all of the plugs an they are getting spark. So once I realize I had spark I started checking the next issue maybe no fuel. I had an issue at the beginning of the season with the fuel pump not pumping, I messed around with some of the grounds and all of a sudden started working. I took this video last night of me trying to crank it. it doesn’t seem to me that this should be enough fuel to start the engine, am I correct? What should I be looking to do? Recheck grounds, replace pump?

 

[Dr Honda]

Fuel coming out a nipple means nothing on an EFI engine. You need to have proper pressure behind the injectors. In your case... that would be 36 PSI.

In your vid... there's a Schrader valve (like on a tire) just to the right of the hose you have off. Put the system together, and check the pressure there.

 

[matthewdandrea]

Dr honda, i jumped the high pressure fuel pumps ground and the boat starts up with fuel pushing to the engine. I traced back the ground wire and it goes to the ecu. Is there another component that Controls that ground to the pump to turn the pump on and off, obviously I cannot jump that wire permanently because then the pump would be on all the time. What should I do next.

Here is the video

 

[Dr Honda]

The ECU controls the ground to turn that pump on and off. I would check the wireing, and fuse on the pump wires (although, the fuse is probably ok since it turns on) but if there's not a bad connection somewhere... then the ECU could be going bad.

With that said... the high pressure pump will spin whenever the engine is running. If that's the only thing keeping you from enjoying the boat... I would put a simple relay on the ground, and have it controlled by the key switch, and bypass the ECU control.