2003 DF140 #4 spark plug fouling due to moisture

[seapro]

I have a 2003 DF140 with 1400 hours that is very clean. I'm thinking the #4 spark plug is fouling due to moisture around the electrode. The symtom is the motor needs extra throttle for initial start. I changed out the plugs and it started fine the first time out. On the next trip, the motor needed extra throttle to start - took 18 seconds at high idle to start firing then would idle fine and start in idle position the rest of the day. This scenario repeated. I located the problem in the #4 cylinder and after pulling the plug I noticed it to be wet. Seems to be water. Compression is 15 pounds higher at 180 pounds in that cylinder. I changed the oil pump out 200 hours ago.
I have recently changed the oil with 75 hours and found a small amount of a milky swirl that came out on the initial draining of the old oil the oil smell like gas is mixed in.
Is there anything I should look into before I pull the head to inspect?
As you can see in the pic the motor is clean for being ran in salt water.

[aquamort]

Very possible a head gasket or the like. Have you done a compression leak down test?
I would be checking the VST also for the float sticking etc causing it to basically flood. Though you said your oil was milky and came out first (which is usually water) i would still check this out. There is a breather hose that comes out the top of the VST that goes into tappet cover.....see if fuel pisses out of it when running.

Good luck

[seapro]

procedures in removing cylinder head

Will I be able to pull cylinder head off the block without removing the block from the holder. Is there anything that might be tricky other than the usual bolts breaking ect...Any help with the end in mind would be appreciated.

[WEDOCQ]

The fuel pump is cam driven and will dump fuel into the crankcase when it starts to go bad. Maybe this is where the fuel smell is coming from in the oil?
-Shawn

[catacom225]

Df 140

Shawn is right on the money. I very slightly pressurized my fuel pump and watched drops of fuel leak out,changed it and no more issues, also a common problem is a bad needle ans seat causing excess fuel to be sent into the crankcase via the vapor return line

[seapro]

In order to remove the cylinder head do I have to remove the power unit as the manual states.

[seapro]

Great info mine is dripping after pressurized. Thanks

[redlowrey]

I think that is the least of your problems by the sound of it, you probably have corrosion around the water jacket on no4 letting water into the combustion chamber.