Engine misfires above 3000 rpm

Nickburf

Cadet
Joined
Nov 4, 2018
Messages
7
Well my starboard engine has the same symptom as my port engine did last fall but carb is good on this one so here we go. 1988 marine power 350 rebuilt with 300 hours, starts and runs idles great. Good oil pressure runs 170 degrees. Will run up to wot (4200 but slightly over propped) and will run on plane at 3200 for 20 mins than starts missing as in fuel starvation. Runs exactly the same on outboard tank connected to fuel pump. New wires, coil, plugs, cap, rotor. Seemed to get slightly better after rotor change. Any thoughts? Thanks in advance.
 

Nickburf

Cadet
Joined
Nov 4, 2018
Messages
7
Update: went for a test ride today and ran at 3500 perfectly for 30 mins, pulled back to 1400 for 10 mins to go through slow area and missed when trying to get back to high rpm. It seems to almost be ok if I gradually increase rpms. It has a steel line from carb to mechanical fuel pump so no easy way to check that I know of,
thanks in advance
 
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