1983 70HP Evinrude bog under load

[vt700guy]

On the way in to the ramp last weekend at 3/4 throttle my engine started bogging. It got to the point where at nearly full throttle it was barely moving. It would rev out just fine in neutral, but would not rev out under a load. Any thoughts?

 

[oldcatamount]

That sounds like an ignition problem. Get yourself an air gap ignition tester and check the spark on each cylinder. The spark should be blue and able to jump at least 3/8". Could be a bad coil (or two) or a bad power pack. A tester will help you figure it out.

 

[Bob_VT]

Even if you have a dropped cylinder or cylinders a 2 stroke will "sound like" it is revving up in neutral and will even register fine on a tachometer.

Yes start out with the basic trouble shooting - spark - compression - carbs ..... if it was running fine and this is all of a sudden then it might be as simple as a wire connection.

 

[vt700guy]

I will grab a spark tester this week and start there. I'll keep you guys updated.

 

[vt700guy]

Just to follow up. Spark and compression were good so I took it to my local boat shop and they rebuilt the carbs. Runs better than ever now.

 

[Bosunsmate]

if that happens another time check that the little ball that swivels in the timing link hasnt fallen out. You get exactly the same symptoms too.
Its the little metal rod that moves with the main control lever on the engine to move the timing lever under the flywheel to advance or retard the timing. Ive had mine pop out a few times, ive an 82

 

[vt700guy]

Thanks for the tip. Might save me from using the oar sometime .