2006 Optimax 225 and I have the 4 beep alarm going off every 2 minutes. Engine is running fine with no hiccups. Other symptom is if it gets over 4000 rpm, the Guardian System kicks in with the continuous beep. Throttling back gets the 4 beeps and then it will beep again in 2 minutes.

Oil level in the onboard tank was a little low. I filled that up. The tank on the outboard itself is full.

I'm thinking it's fuel filter and/or water separator.
I can't find anything that tells me how or where to check/change the fuel separator. Is that the same thing as the fuel filter? If not, can someone guide me to how to check/change the fuel separator please.

Thanks!

Its on the port side right next to the fuel pump. The fuel/water filter has a wire on the bottom that is for the water alarm.

Just pull the wire loose and put a strap wrench on the the filter. It should come off easily. Replace it with a new filter and sensor or take the sensor off the old filter and put it on the new one.

Optimax does not have that filter Allison. #10 here: http://www.boats.net/parts/search/Merc/H...ENTS/parts.html You need to have a special tool. You can buy the filter with a tool: http://www.ebay.com/itm/Fuel-Filter-Remo...cba&vxp=mtr

Go ahead and replace the fuel filter. But I bet you will end up having to replace the engine mounted oil tank.

I have the fuel filter and will change tomorrow. Would the alarm continue to go off and the engine run normally if the on board oil tank was defective?

It could be water in fuel but more than likely is the float inside the engine mounted oil tank. By the way if it happens to be water in fuel, replacing the fuel filter won't fix the problem because the water in fuel sensor on your motor is threaded into the bottom of the vst tank. And to answer your question about the motor running normal. The float sensor in that tank has a low oil level and a critically low level. Low level will give 4 beeps every two min and critically low level will put it into gaurdian mode. Just because there is oil in that tank doesn't mean the float sensor is working.

As predicted, fuel filter didn't cure the ills.

Next stop?

Oil tank w/sensor. If you did not clean out under the fuel filter with a suction bulb when changing you could have the same problem.

Thanks everyone. Had some 'phone a friend' help from a very helpful TFFer who walked me through changing the oil reservoir and bleeding the system.
No more beeps.

Thanks again, friendly TFFer.