1968 Evinrude 85 Issues

sdfishman

Recruit
Joined
Nov 6, 2005
Messages
3
I'm pretty new to the world of 2-stroke engines, so let me plead ignorance in advance, but any insight that could be lended to my current situation would be greatly appreciated!<br /><br />I picked up an old Mark Twain runabout with a 1968 85hp Evinrude on it. She fires up, remains cool, compression is good, but I'm having a bit of a problem.<br /><br />In neutral, it runs relatively well, the throttle is responsive, feels fairly smooth. Once I put it gear, however, the engine bogs down somethin fierce, if I manage to keep it running, the throttle is almost completely unresponsive.<br /><br />Where might be a good place to start?<br /><br />Thanks in advance.
 

Joe Reeves

Supreme Mariner
Joined
Feb 24, 2002
Messages
13,262
Re: 1968 Evinrude 85 Issues

Compression should be 100+ psi and even on all cylinders. Is it?<br /><br />With s/plugs out, spark should jump a 1/4" gap on that model with a strong blue lightning like flame.... a real SNAP! Does it?<br /><br />If the above checks out okay, that type problem is usually due to fouled, clogged carburetors or a sticking timer base (spark advance) under the flywheel.
 

sdfishman

Recruit
Joined
Nov 6, 2005
Messages
3
Re: 1968 Evinrude 85 Issues

Thanks Joe.<br /><br />Compression was 100 at two cylinders, and 95 at the other 2.<br /><br />I will have a look at the other potentials you listed.
 
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