intermitent power loss

I have a 1987 Merc Black Max and that I inherited from my father. It had been sitting for a year or so and the fuel gauge doesn't work very well and I recently ran it out of gas on idle. After I filled it back up I took it out and once at full power it keeps hitting short 5-10 second spots of losing RPM's and power then it kicks back up where it is supposed to be, runs great for 30 seconds or so and then another short dip in power. Seems like it's not getting fuel properly. I know nothing about outboards and what I've been told about this engine is to run it until it starts beeping and then bring it in. Could this be a simple fuel filter issue or does it need some fuel cleaner maybe?????

Re: intermitent power loss

scott, welcome to iboats, where you can get a free education. first a couple of questions. post serial #? you say it sat for a year, did you use new gas or the old gas when you ran it? did it do this the first time out? assuming the fuel guage doesn't work well, you have a built in fuel tank. is there a fuel/water separator/filter? have you changed the filter? you may not have run out of gas, but pick up water/trash out of the old fuel. do you have a mercury service manual that is for your specific year & model? post these answers, and we'll follow up. keep your post on the same thread, they are easier to follow, and readers get all the history.

Re: intermitent power loss

The place to start is get some carb and fuel injecter cleaner and run that thru the fuel system, change or clean fuel screens or filters and if that don't work clean the carbs.

Re: intermitent power loss

check the screws that hold the coils on. loose screw will do same symptom. did on mine, good luck ron

Re: intermitent power loss

if it was me think i would look at electrical things first dirty loose scuffed wires