Mariner 115 HP inline 6 power trim CDI ignition TOO much fuel

[andersonspartsplus]

198? Mariner 115 HP inline 6 power trim CDI ignition

Put the boat in the water, let it warm up and took off. It ran great on the trip across the lake. Throttled it down for a minute and then back to WOT and it fell on its face. I blurped the choke to see if it was lean and it died. Fired right back up, but the problem was still there.

Sparks plugs are soaking wet all the time. Motor idles and revs fine in neutral, sputters at midrange and boggs at WOT. Using a very excessive amount of fuel. No leaks around the outside of the fuel pump.

All 6 plugs have spark. Even swapped in new plugs...same same.

So my question is could a bad fuel pump be leaking to much into the crank case? Or could the carb internals be causing these symptoms?

At any RPM in and out of gear when I shut it down and pull the plugs all 6 are soaking wet with fuel.

Any idea what would cause these symptoms?

I am very familiar with all other manner of engines both 2 and 4 stroke, not a lot of experiance with outboards.

 

[bgc]

Re: Mariner 115 HP inline 6 power trim CDI ignition TOO much fuel

Check the ;
Needle and Seat
Float
Idle adjustment
Fuel pump diaphragm

 

[CharlieB]

Re: Mariner 115 HP inline 6 power trim CDI ignition TOO much fuel

Can you get over 2500 - 3000 IN gear and IN the water?

Reving in Neutral or on the hose don't count, it has to be while under load.

DVA test the high speed windings of the stator, if they fail, motor performance/power is gone much above 2500 and the pllugs will appear wet as there is insufficient spark to burn it.

 

[CharlieB]

Re: Mariner 115 HP inline 6 power trim CDI ignition TOO much fuel

Oh, and do NOT assume it is the stator and order the costly part without PROVING THE FAULT, as there is NO RETURN on electrical parts, you want to be certain that is it before spending your money.

 

[andersonspartsplus]

Re: Mariner 115 HP inline 6 power trim CDI ignition TOO much fuel

Could a bad fuel pump diaphragm cause too much fuel to enter the engine.

 

[CharlieB]

Re: Mariner 115 HP inline 6 power trim CDI ignition TOO much fuel

Usually a leaking fuel pump will only flood the cyl that operates the pump(s).

The recirc system will try to spread any excess fuel out but not so much or so fast as to have a flooding effect on all cyls.

If the motor has a weak high speed ignition it will not be able to burn the normal amount of fuel flow from the carbs, RPM and power will just 'hang', the motor bogs and will not accelerate any further, wetting the plugs and acting like it is flooding.

A simple test, use an inductive timing light, see if the light starts to fail to flash when the condition begins, indicating a weak spark.

Then get a hold of a DVA meter or a DVA adapter for any volt/ohm meter and test the high speed windings as spelled out in the service manual or the CDIElectronics Ignition Troubleshooting Guide.