[retired teacher]

I've been given a 25 hp mercury motor, serial # 0D172586, I think 1992 or 1993 model. It starts fine but is sluggish running. I've cleaned the carb but don't know the recommended factory needle setting. Can someone provide the recommended setting?

[mthieme]

Does it idle okay?

[retired teacher]

Idles okay. Sluggish on take off. I don't have a manual and was wondering as to what mercury suggested to turn the needle for a beginning point.

[mthieme]

Typically it's 1.5 to 2 turns as a starting point.
Also, every Merc I've ever had was finicky with the adjustment...just my luck. There was a definite sweetspot.
Unfortunately, I don't have a 2 cylinder manual (as many as I have I should be ashamed - or a little less tight!).
I do have a 3 cylinder manual I can check later if noone chimes in.
I probably have rebuild papers laying around the shop too that might say (never read one).

[Silvertip]

If the engine idles (rough or not) you have a starting point. Slowly, 1/8 turn at a time on each carb, turn the mixture screw in. The engine may begin to smooth out and speed up which means the initial setting was rich. Or it may begin to slow and run rougher which means the original setting was lean. If the engine begins to smooth, continue turning the screw until the engine begins to slow and gag. Note the position of the screw and then go the other way 1/8 turn until the engine again smooths. Continue in the out direction until the engine begins to run rough and slow down and note that position. The best idle setting is somewhere between these two points. With the engine in the water (not on muffs because there is no back pressure) adjust the idle speed to spec. Put the engine in gear and go full throttle in one quick movement of the throttle. If the engine gags, richen (turn the screw out 1/8 turn) and repeat the process until it does transition from idle to full throttle without coughing or spitting. Finally, readjust the idle speed, in gear, at idle, to spec.

[retired teacher]

Appreciate your help. In the tank it appears to run smooth somewhere near 1 1/2 turns. As soon as I can get it on the lake, I'll try and make the necessary adjustments to take out the hesitation and sluggish take off. Without the manual, I didn't know what Mercury recommended. Thanks again.