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40 hp two stroke losing power

D

dalefan4lyf

Member
I have a 1995 40 hp Mercury 2 stroke and here is the issue. We got it from a family member and it sat for about 6 years. Cleaned it up, took it out and it lost power after about 10 minutes of full run time had to idle it back to dock. Rebuilt the fuel pump and found one of the rubber diaprams that looked blistered. hit it with some Stabil and gumout and tried it out in the drive way. Started like a charm. Took it out to the lake. Ran for about 30 minutes and same issue as before only it was very hard to start and if i put it in gear it died. I am dumb founded.
 
...it sat for about 6 years.
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Jeff is right about the carbs. Six years of sitting has probably left fuel varnish deposits in the entire fuel system. The fuel tank hose connector on the engine can also be plugged reducing fuel flow to the carbs. Have you cleaned out the fuel tanks? Crud from them and from the rubber fuel line will keep causing carb problems.
 
UPDATE: I was looking over the motor tonight, planning on how to pull the carbs. I noticed an oil puddle on the ground. Further inspection revealed that the tube that feeds oil from the injection pump to the fuel T is broken away and laying in the bottom of the motor pan. So with no oil in the fuel is my 2-stroke trashed? It still turns freely. Did no oil cause it to loose power from overheating? Geeez, I feel like an idiot.
 
Does not sound good at all.------I guess it is too late to have a shop get it ready to run for you.---------------If it ran at full throttle for 30 minutes without oil you may be looking for another motor.
 
With my gauge I would get about 120 on that motor.----------------------Remove bypass covers and inspect pistons and rings.------------------------I am sure that you need to rebuild / replace the motor.
 
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