Problem with Mercury 250XB

[Brucet84]

Don, I have a 2002 Mercury 250XB. Last week I put it on the water and when I started it up I got a beep - beep - beep signal. I had no idea what it meant. I started across the lake, got up to 55 -60 mph. After about 5 minutes the engine began to surge and sputter and then shut down. It restarted a few minutes later only do do the same thing after about 1/2 mile. I trolled back to ramp and took it home. Everything looked good except the plugs looked fuel fouled/rich. I replaced the plugs, went back to the lake and got the same result. I don't think there is any damage to motor at this point but I need to figure out the problem and fix it. I think it may be a fuel problem but not sure. I replaced the fuel filter and lines from the tank to the filter last fall. The old grey fuel line had come apart on the inside and had clogged the filter.I am very mechanically inclined and can fix about anything IF I know where the problem is. My job and paycheck have been cut way back so I can't go to a dealer unless it is ABSOLUTELY necessary. Any help or advice will be greatly appreciated ! email brucet84@aol.com or my cell is 888-812-9503 Thanks ! Bruce

[EuropeanAM]

The type of warning horn signal you received indicates one of the following:

-WATER IN FUEL
-LOW OIL LEVEL IN ENGINE MOUNTED OIL TANK

The engine mounted oil tank is simple to check... it should be FULL TO THE BRIM, with ABSOLUTELY NO AIR PRESENT.

Remove water separating filter, and pour contents into a GLASS JAR. Watch for separation of contents.

IF no separation is noted, ADD SOME FRESH GAS TO THE JAR. If the fuel sits ATOP the contents- it's WATER!

If water is noted- DRAIN FUEL TANK COMPLETELY DRY, and START WITH A FRESH LOAD OF FUEL.

Your engine doesn't run well on water (if at all).

[Brucet84]

I will give it a try. Thank you VERY MUCH for the help ! Bruce

[ThunderCat]

Let us know what happened bruce...

[herk91]

will the engine automatically prime the tank located under the cowling when it is first started or do you need to fill the tank from the top before starting?

[low slung cruiser]

it can fill itself, but i would definately go ahead and fill by hand...you're supposed to be able to crank engine, and slowly remove the engine mounted tanks cap till it fills the tank up with the oil...BUT again, its alot faster to just do by hand and you know its full...

[EuropeanAM]

Please see the following post on bleeding air from the engine-mounted oil tank:

http://www.bbcboards.net/zerot...esent

[Brucet84]

Don, I checked the gas and can find NO water. ( I use Sea Foam pretty regular.)
I also replaced all the fuel lines and fuel filter. Put in new plugs. Oil tank on side of engine was full and I saw no leaks so I didn't open it. Went to the lake today. It jumped up on plane and ran like a scalded dog for about one and one half miles. Then it began to sputter ( cut out ) and died completely. All in 20-30 seconds. The fuel bulb was still tight. I waited about ten minutes and it would not start until I disconnected the black wire with yellow stripe on starboard side. I was told it would over ride the starter switch and the lanyard switch. It started up again and ran great for about a mile and a half. Same problem as before. This time it wouldn't restart. I trolled back to ramp and loaded it up.
Any ideas ? I am willing to try whatever you think I need to do. Thanks , I appreciate your help ! Bruce

[modvp]

Check the connection for the temperature sender at the back of the engine. I had a similar problem (with the beeps) when the black to brown wire was inadvertently disconnected.

[JAZII]

Sounds fuel related.
Bad fuel line, fuel pump problems, or gas tank vent blocked.
The KILL SWITCH wire was not the problem.

JAZII

[EuropeanAM]

Bruce:

I'd plan another water trip.... with a TIMING LIGHT and a FUEL PRESSURE GAUGE.

When it acts up- connect BOTH, and determine if it's a SPARK PROBLEM (timing light won't flash) or a FUEL PRESSURE problem (no or very low/unstable fuel pressure).

This will help to narrow down the field of possibilities.