1988 Mercury EFI 220 V6

[Nicholasr]

I can use some help out there, I have been battling raw fuel leak coming out the exhaust and I just can't find the problem.

I bought my boat about 3 months ago and here is what has transpired:

I had no real power, once I put the boat in the water and could not figure out what could be causing it. I took it to a boat mechanic shop and he tied it up for 4 weeks. I got so frustrated with the service that was being done, I went and picked it up. He could never give me an answer or a phone call. He took out my injectors and sent them out to be checked and cleaned.

Once I got involved, I realized the fuel separator was never checked, cleaned or replaced. I did this and realized a big difference for a short period of time. Once in the water under power and with a load, I realized raw fuel was leaking from the exhaust. I don't mean oil, raw fuel mixed you can smell it. I took the boat out and replaced the main fuel filter and the fuel pressure regulator.

Tomorrow I am going to check for spark, rebuild the manual fuel pump, check the pressure from the electronic fuel pump.
NOW it was suggested that maybe one or a few of my injectors were stuck open???

Can a Mercury tech give me some feedback
Thanks Nicholasr

[rock]

Does the motor seem to run ok? How extensive is the amount of fuel? Any 2 stroke motor is going to dump some raw fuel out the exhaust.

Rock

[Nicholasr]

Does the motor seem to run ok? How extensive is the amount of fuel? Any 2 stroke motor is going to dump some raw fuel out the exhaust.

Rock

Thank you for the response, engine starts right up and runs fine, until I put it into gear. no power 1500 RPM's and the amount of fuel is substantial

[Nicholasr]

compression is good

[rock]

Do you know who did the injectors? I think your looking in the right direction. I would check fuel pressure to verify regulator is working correctly. It would be nice if you could find another 2.4 ecu to try. That's some early efi stuff there. Good luck and welcome to the site.

Rock

[Nicholasr]

Do you know who did the injectors? I think your looking in the right direction. I would check fuel pressure to verify regulator is working correctly. It would be nice if you could find another 2.4 ecu to try. That's some early efi stuff there. Good luck and welcome to the site.

Rock

I'm not very happy with the person who did the injectors; I'll leave that part alone.

Is it possible for an injector to be cracked or stuck open? would this cause fuel to leak into the manifold and out the exhaust?

[rock]

Knowing the true condition of the injectors is important. I regularly use Power Performance in Florida. Very reasonable turn around and cost. It is very possible for an injector to stick open and it would certainly dump a bunch of fuel.

Rock

[tlwjkw]

It would be nice if you could find another 2.4 ecu to try. That's some early efi stuff there. Good luck and welcome to the site.

Rock

.......

might be a chore ta find a "good, working" replacement ecu for it... first gen efi's (pre 2.5) used tha 14632A2, 6 and 7 which really sucks even when it was new.. could easily make a carb motor run better back then..........

fire (switch boxes, stator, trigger, stabilizer etc), tpi, fuel pressure could all be suspect also.. need ta do a thorough investigation of all of it.........

raw fuel sounds more like a firin' problem ta me anyway............ jmo

[Go Time]

Definitely check your ignition...I betting the high end of the stator is bad. There could be other issues, but raw fuel will accumulate in dead cylinders.

[Nicholasr]

Definitely check your ignition...I betting the high end of the stator is bad. There could be other issues, but raw fuel will accumulate in dead cylinders.

Rock, you were the only one with me on this. I found the problem today!!!!!
The guy who did the injector jon lost a bushing for the Fuel Rail Pressure Port! a $4.00 part

I opened up the cover, turned the key on and let the pump pressurize the system and gas came shooting out the port

For 2 weeks I have been trying to figure out this problem

[Nicholasr]

Rock, you were the only one with me on this. I found the problem today!!!!!
The guy who did the injector jon lost a bushing for the Fuel Rail Pressure Port! a $4.00 part

I opened up the cover, turned the key on and let the pump pressurize the system and gas came shooting out the port

For 2 weeks I have been trying to figure out this problem

[Go Time]

Hard to believe the engine ran fine at idle with all that fuel leaking into the intake....oh well, learn something new every day.
You would be surprised how many fuel problems turn out to be ignition problems. Glad you got it fixed. Let us know how it runs.

[rock]

Congratulations. Ya did it yourself and are now a bit more familiar with your motor. Good job.

Rock