65hp Mercury outboard not running right, help

BIGDOG2594

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Jun 23, 2008
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I believe the engine is a 1975 650 or 65 hp Mercury outboard. Engine has ran fine for several outings. Then one day the engine decides it just doesn't want to "get up". We stopped for a bit and then it ran fine again. Figured it must just be some water in it from the bad rain we had the night before going out. NOw, we get out this past Saturday (first time running since we had the first signs of problems) and the engine runs fine to the fist fishing spot. Then when we get ready to head to the next spot, it just won't "get up". With full throttle open, we are going about half throttle it feels like. No real skipping or miss-firing sounds, just complete lack of power. It ended up burning right through the gas and had to be towed in. No other signs of any problems, just lack of power. We checked the spark plugs which look to be ok. The distributor cap looks like the points are corroded or something. Nothing other than some connections should be cleaned looks out of place. Can anyone relate or send us in a direction so that we can get this motor back? No one in our area can look at it till the end of August, end of the season pretty much.
 

Laddies

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Sep 10, 2004
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Re: 65hp Mercury outboard not running right, help

Mercury marine did not build 65 HP engine with standaed ign. in 1975 so we need to start with better info.
 

BIGDOG2594

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Joined
Jun 23, 2008
Messages
13
Re: 65hp Mercury outboard not running right, help

Not sure what you are saying. I haven't checked the serial number yet, but I am pretty sure by the descriptions and pictures I find. I found these model numbers with an electric start, 4136685 - 7051133 in 1975. It has a black with blue casing and the rest of the motor is black.
Here is the casing:
http://www.oldmercs.com/1975Merc650cover.JPG
 
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