Merc 225/EFI 1997

[jerryjerry05]

I have a problem!! It starts and runs good at an idle.It runs up to 1700rpm then bogs like it aint getting fuel.The filters are clean,no water in the filters,the 1st pump has been rebuilt,the electric pump(in the vaporizer) works and it's filter is clean.It has 42# of pressure at any operating RPM.The book says it should be 34-36# What's the next step?

Thanks,J

 

[CharlieB]

Re: Merc 225/EFI 1997

Making fuel pressure with no load is easy, making that pressure while under load and requiring a LOT of fuel is another story.

Start with the fuel tank fittings and dip tube, take them completely out of the boat, apart, and inspect for any debris that may be restricting fuel flow.

Once back together, take the fuel line of the primary fuel pump, attach an electric pump and point it into a suitable container, turn on the electric pump and watch the flow, looking for a good 3/8's inch solid stream with NO air bubbles, to confirm a good fuel supply to the primary pump.

Remove the electric pump and reconnect the fuel line to the primary pump, disconnect the fuel line AFTER the primary pump, point that into a suitable container, pull the lanyard so the motor will NOT start. Crank and observe the fuel flow from the primary pump, it should be almost the same as with the electric pump but noticeably pulsed.

Reconnect the fuel line, test drive.

Repost any problems.

 

[jerryjerry05]

Re: Merc 225/EFI 1997

The tests were done under load in the river.The fuel system is clean.I have a primary water/fuel seperating filter and a second one on the motor.I also put in a particle filter(just in case).Flow is not a problem.I rebuilt the pulse pump(just in case).
The electric pump is working 42#of pressure ,manual says 34-36#.The regulator is alowing too much pressure.Before I spend 250$ for a new one I wanted to cover all bases. Thanks for the reply.J

 

[Sandjob]

Re: Merc 225/EFI 1997

just FyI. If your merc has under cowling water/fuel seperator it is not suggested by merc to run an additional. It creates unnecessary draw on the pump.

 

[jerryjerry05]

Re: Merc 225/EFI 1997

Bump,J