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1978 Evinrude 70HP being a little bitch

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billythegrape

Contributing Member
Picked up an Evinrude 70873c long shaft to replace the short shaft 50 I had that was coming out of the water every 2 seconds on my 24' pontoon. Motor was fabulous for the first 4 miles, then lost power and ran ****ty. Seemed to be sucking so much gas that the fuel filter had to be manually filled.

Stator and rectifier were melted; replaced them and timed ignition to 15 degrees (2 below 17 spec; it was at 13 degrees). Went out on the lake for the day; ran ok, but not a lot of power. Almost like it's being held back.

Changed fp, replaced all fuel lines, and rebuilt carbs as motor was purported to have been sitting for some time and hoses were all ****ty looking. Put it on muffs, idles, but again seems to not have full power.

Plugs are soaked. When I rebuilt the carbs, the bowls had a couple of drops of water in them. Does this mean my gas has water in it?
 
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Nevermind, I think I figured it out. The advance was not reaching the bumper on full throttle. I adjusted the throttle cable and now it is touching and seems to get full power. Will hit the lake and let you know.
 
Or warped exhaust covers ( very common ) on those.----Your cylinder head iis warped as well.----Plastic parts melted ??----Inspect cylinders walls before spending the beer tokens on this motor.
 
racerone said:
Or warped exhaust covers ( very common ) on those.----Your cylinder head iis warped as well.----Plastic parts melted ??----Inspect cylinders walls before spending the beer tokens on this motor.
Click to expand...

Cylinder walls look great. Already got the parts coming. I didn't overheat this; it looks like it happened some time ago. Will check the head for warpage after cleaning. head gasket was ridiculously corroded.
 
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