1997 Mercury EFI 225 HP help

AErcen

Recruit
Joined
Jan 24, 2008
Messages
4
When I prime the fuel system, all the fuel that is being pushed is coming out of the throttle body. ( for lack of better word, I want to say the fuel is coming out of the carbs). I know it has no carburators, but the butterfly valves that open up is where the fuel is pouring out.

Bulb pushes plenty of fuel, it never gets hard, there is no resistance..It just pours out the carbs.

The engine will not fire.. It cranks and cranks, but will not fire. I am reluctant to look for ignition problems until I can satisfy myself with the fuel pouring out the throttle body.

I replaced the fuel, fuel filter.Batteries are brand new.I am amazed at the ease of fuel just pouring out the carbs. The fuel filter, fuel pump, and I suppose the injection pump is not providing ANY resistance..

Does anyone have a reasonable guess for an amateur to tackle this ?

Thanks.
 

rodbolt

Supreme Mariner
Joined
Sep 1, 2003
Messages
20,066
Re: 1997 Mercury EFI 225 HP help

look at the top of the vapor seperator.
trace the VST vent line back to the intake assy.
unplug it,pump the bulb and if fuel flows you have a leaking VST needle valve or a sunk float.
can also be a ruptured diaphram on the rail assy.
unplug the vacum line from the regulator,if fuel is there, carefully test the regulator.
all your primer bulb does is fill the VST,until the key is turned on the high pressure pump and injectors are not the issue.
also check the fuel lift pump diaphram.
usually when blown 2 cylinders fill with fuel and it runs nasty.
 

AErcen

Recruit
Joined
Jan 24, 2008
Messages
4
Re: 1997 Mercury EFI 225 HP help

Thanks for the detailed info. Since I have not done any work on outboards before, I think I am going to have to have the professionals look at it.
I got as far as "VST" and realized a man has to know is limitations!

I guess sitting and not being used is not good for these things..

Thanks again.
 
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