Just rebuilt a 1986 Merc. 150. 115 psi compression on all cylinders. Cylinders 3 and 4 were bored .020 over with new pistons. Rest of block was in good shape. All new rod bearing. It was running very rough so I replaced both the stator and trigger. Put on another set of ignition moduals. Runs great on the hose at home. It has great RPM range with all plugs firing. Put on the lake and no power at 1/4 to wide open throtle. All plugs are still firing. While under load, I spray the carbs with more fuel and no increase in RPM's. I sprayed down block with carb cleaner when running and and had no change in RPM's. ( looking for vacuum leak )
Any and all help will be helpful. Thanks diverman
Any and all help will be helpful. Thanks diverman
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