Mercury 25 ho bigfoot 4 stroke

by Mark
(grafton ma)

Hello all . I have a 01 mercury 25hp carbbed 4 stroke.this has always had a slight hestation at about 1/8 throttle to 1/4 throttle.if yiu go slowly through this range it hesitates but doesnt stall. If yiu do a hole shot it will stall.fisrstcthing I did us rebuild the carb . I siaked in Berryman ckeaner for two days . It then went through an ultrasonic cleaner. I then fished all jet holes out blew out with carb cleaner and compressed air and rebuilt.just fyi carb was near spotless before rebuild. I the rebuilt fuel pump and did a tyne up. Alm oem stuff. I ohmed enricher valve it checked ok. I pit voltage to it and waited a few mins and it went to its specified range. I tested one of the yellow wires going to it and with engine running there is 37vto 52 volts dc going down the wire. Im a small engine mechanic and this usually us corrected by opening a low speed jet a little or opening an air screw a little. My carb does have an air screw it helped a little by playing with it but it's still there. No where in manual does it tell you were to set it. I also have new merc fuel line connectors and primer ball.the engine runs flawless everywere else . Its just something that doesn't seem right i dk alot of trolling and if the conditions are right I sometimes need to be in that band.any ideas would be appreciated