1976 evinrude 85 hp fine tune?

[matt85evinrude]

how do i fine tune the engine? it runs fine and smooth at idle but when you rev it up from 3500 rpm onwards it has a miss going on! have only run engine out of water will this make a diffrence? the lync and sync in my service manual is pretty vague. thanks.

 

[emdsapmgr]

Re: 1976 evinrude 85 hp fine tune?

You can easily check the spark with an inductive timing light. The flashes in the gun will tell the story on each plugwire. Take a friend out boating with you to run the boat when you test it in gear at rpm. If the spark looks, rhythmic and solid on all 4 wires at all rpm's, you may have issues with fuel.

 

[crb478]

Re: 1976 evinrude 85 hp fine tune?

Dont run the engine to 3500 rpm out of the water, you may end up with a run away engine which will quickly blow if you don't strave it for air/fuel. Limit it to less than 1500 rpm out of the water. Take it to the water and see how it runs with the correct back pressure. You might be trying to fix something thats not broke.