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60hp 2 stroke rough midrange

Pinboy122

New member
I have a 1997 merc 60hp 2 stroke ser# OG4823...
i just put this used engine on my pontoon and can’t get a rough midrange solved. It runs rough like a cylinder is cutting out from just above idle and up to 3000rpm. It starts great and runs wide open without a flaw. When it’s running rough it also shakes or vibrates bad enough to feel in the boat and on the steering wheel.
What I’ve done:
new fuel lines ball and fittings. Checked the intank pickup and removed a stiff antisiphon valve.
New spark plugs and changed 1 bad wire.plugs seem oily and kinda wet.
Used timing light to try and find weak or intermittent spark, looks good.
Disconnected plug wires 1 at a time while running and can’t find any real difference.
Compression 125 across the board.
Have paperwork stating that carbs rebuilt and stator changed last year.
I have a complete parts motor but unsure where to head next? Coil? Trigger?
Has anyone had a similar issue?

thanks,Al
 
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