My 1977 Evinrude 3 cylinder 70 hp hesitates on acceleration and often stalls around the mid point of travel even if I slowly increase the throttle. On occasion when I shove the throttle quickly through the mid-point the engine will take off. If it makes it through this mid-range without stalling it seems to run fine. Briefly putting on the choke definitely causes it to stall so it appears like it may be getting plenty if not too much gas so I think the fuel pump is OK. I have loosened the gas cap with no effect. The compression is good and matched between the cylinders. At idle the cam follower is centered on the lower line (the line that doesn?t have START printed on it. Based on my understanding of the service manual the lync & sync are set properly. Since it runs fine at higher speeds I haven't attempted to check the timing.
