2002 Mercury Optimax bogs down @ approx 1500 RPM?

Question

I have an optimax that idles fine. OIl systems works as well as cooling water. For all intensive purposes a great motor. Problem is when I put it under a load @approx 1500 RPM it boggs down. I have been told that the four alarms I hear is either fuel or oil. I know its not oil so what could be causing my motor to do this? It is intermittent. Sometimes I can do 80..other times 25. I usually have to slowly increase speed to get there and almost always have to disconnet fuel line and plug it back in. I am seeing bubbles in my fuel. Has anyone experienced this issue? PLease help...the fish are biting

Answer 1

It needs a carb job. The carb is gummed up and needs to be cleaned. The highend jets are stopped up and not giving it enough fuel. The low end jets are working great and therefore idling smoothly.

Answer 2

check exhaust system, might be clogger by a  bad muffler or catylic converter...to find out it thats it, unhook eaxaust pipes from manifold...if car runs great thats it....also if it is the catylic converter it should be under warrenty, 8yrs. it is a federal mandate

Answer 3

Sounds to me you are getting air in your fuel system. The fuel pump will always pump air in preference to fuel, it is lighter.

Suggest you check all fuel connections from your fuel tank to your engine. Just because you get no leaks when you use your primer bulb doest mean you don't have a leak before the primer.

Also check the rubber ring for sealing on your fuel filters on the outboard and in the boat. This problem is more common than you would think.

Good luck

Answer 4

Sounds to me like your fuel system is depressurizing, which can, in turn, burn your engine up. The pressure in those fuel lines is what makes an Optimax an Optimax. Also, in some of those Mercury outboards, they had a vinyl gear that was mated to the crankshaft that runs the oil pump, and if that vinyl gear is stripped, you're losing oil pressure and that might also be the cause of your alarm. BUT, before you start diagnosing the problem, try replacing the fuel line first (start cheap, right?) and then go from there. If you're getting air, then it sounds to me like you might also have a bad seal on the fuel line. Change the line, then go from there. I'd more than likely take it to the Mercury dealer so that they can plug it into the computer and run it at the same time to read pressurizations and engine diagnostics.

Answer 5

If you haven't changed the fuel filter recently, change it.  Hopefully this will correct the problem.

Answer 6

This is a outboard motor for a boat not a car engine. Sounds like something with the fuel systen...Check the fuel lines for leaks that could permit air intrusion into the fuel system. If there is a vent on top of your fuel tank or in the fuel cap be sure it is clean and free of debris, if its clogged a vacuum will be pulled in the tank causing the fuel not to flow. If theres an electric fuel pump used(unlikely) make sure its pumping properly. Also, check or replace the basics: fuel filter, Air intake and exhaust restrictions, Clean sparkplugs and check for proper spark gap and replace if necessary(if original 2002 I would change them out anyway. Try running some fuel system cleaner thru the tank. Thats all I can think of for now but its a place to start.

Answer 7

The 4 alarms your hearing i assume are 4 beeps of the warning horn and then nothing for two minutes then another 4 beeps, etc.    This alarm indicates one of two things, low oil in the on the engine oil reservoir, or water in the fuel.  You said you have checked the oil injection system.  So you may have water in your fuel tank.

There is a black metal can on the forward port side of the engine that has a wire on the bottom of it,

(be careful it is full of  gasoline!!)

Remove it and empty it into a clean container.  If it seems like there are 2 liquids in the container instead of one (sitting on top of the other) then you have water in your fuel.   Hopefully you only have a little, but by the sounds of it, you have been running your engine with  water in it for a while, i would advise taking it to a good marine mechanic  to get all the water cleaned from the main fuel tank,  VST tank, fuel pumps, rails and lines