1969 yachtwin 4hp running RPMs

[sclservice]

I have a 69 yachtwin 4 hp just got through replacing points, ignition coils etc, cleaned the carb, cleaned the fuel system parts, unit starts right up 1-2 pulls & runs at high speeds full bore but when you put the cowling on the RPMs drop like it is starving for air. Also in order to run at low speeds you have to pull the choke out a bit and it runs fine. Made all the high & low speed adjustments according to the manual and tweaked a bit but this still persists. Starving for gas? Adj. needles & seats need replacement? Any ideas???

Thanks in advance

[boats.net]

Could be low on compression, air leak in crankcase or intake or plugged p***ages in carb.