1976 Evinrude 85hp no start in lake but starts on muffs

[Automan14]

The couple mornings ago we went to put my boat on the lake and no start. It sounded like it was cranking fast enough. But I pull the cowl and checked for spark and wasn’t get anything. So I took it home and in the drive way it fired off instantly. I live like 5 mins from the lake so I went back to the ramp. And no start again. I checked compression and got 115 on cylinder 1&3 and 110 on 2&4. The only thing I can think of is maybe my battery. But I’m stumped

 

[racerone]

Load test the battery.----Take starter apart for inspection.----Check battery cables / connections.

 

[fdrgator]

Look for leaking charge coils under the flywheel. If you see goo dripping out from them, there's your problem. "Charge" coils mean that they charge the capacitor in the ignition system.

 

[faztbullet]

Load test the battery.----Take starter apart for inspection.----Check battery cables / connections.

Agree...Got to spin fast enough to overcome backpressure. Engine spinning 100 RPM less than needed will not start in water,

 

[Automan14]

Thanks guys. I got the battery load tested and it was bad. Had the boat out the other day and it started great every time

 

[racerone]

Simple is what I say.