Mercury Optimax 250 M2

[ajaquino]

Im having some fuel issues with my Optimax 250…I appreciate all the help!!!! Anyways, seems like my engine is not getting the fuel from the gas tank. Ive replaced all lines, the primer bulb, the fuel water separator, and the lift pump responsible for bringing the fuel up from the tank. When I start the engine to ON, I can hear the pump activate and work. My engine fires up and run for about 5minuted but eventually dies. When it dies, the primer bulb is no longer hard to squeeze. In order for me to restart my boat, I need to manually pump primer bulb to get fuel up….then engine dies again after few minutes. Ive directed my lines straight from gas tank to my pump and was told by a marina mechanic all I need is to turn engine on and off in order for the pump to suck fuel up. Ive tried that several times and seems no fuel is coming up and engine doesnt start, but tries to start with no luck. Please help as my boating season is looking crappy and crappy everyday with this problem. And all marinas are backed up 4wks by me. Thank you!

 

[biffdotorg]

Like the 240 EFI, don't those motors have like 3 fuel pumps? Two low pressure and one high pressure for the fuel rail? I think guys on the SeaDoo forum in the Merc section are real sharp with pressure testing the fuel system.

Good luck

 

[Bilmon]

check tank vent and make sure it's clear

 

[ajaquino]

Where is the tank vent? Is that part of vst?

 

[ajaquino]

Yes these motors have like 3 pumps so im curious if I need to change other pumps?

 

[ajaquino]

Just disconnect lift pump outlet and tried turning ignition….no fuel coming out. This is a new lift pump…anyone know how much voltage should be output on lift plug? Curious if its getting power

 

[Bilmon]

Just disconnect lift pump outlet and tried turning ignition….no fuel coming out. This is a new lift pump…anyone know how much voltage should be output on lift plug? Curious if its getting power

I assume it's a 12v pump. Don't know if your Opti is the same but my 240 has a 3amp inline fuse in the lead to the lift pump.

 

[ajaquino]

So correct seems like fuse was shot and replaced and lift pump functions now. Only concern, it was a 5amp fuse and i ran it for few minutes but now seems new fuse looks like its starting to break.