1996 Johnson 70hp carburetor intermediate orifice question

abody711

Cadet
Joined
May 15, 2009
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Picked up a 98 pontoon boat with a 96 Johnson 70hp on it. Previous owner stated the engine was rebuilt 3 years ago. After running the boat a couple of times, I noticed a mid-range and WOT bog. Backing of the throttle will allow the motor to come up to 5500 RPM. All cyls have 100+ compression.

I found the top carb had a plug in the intermediate orifice. Checked and found the correct orifice size was 60. Purchased a orifice and replaced the plug. The motor does not want to idle with the change. Anyone have any ideas how to proceed or should I leave well enough alone? I have service manual.
 
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