1997 Johnson/Evinrude EU 25, 35 HP 3-Cylinder outboards Service Manual, Page 40Get this manual
4Stop the engineTo adjust, loosen the idle stop screw locknutRotate the idle stop screw to achieve ATDC idle timing, then tighten locknut Rotating the idle stop screw clockwise advances idle timing Rotating the idle stop screw counterclockwise retards idle timing
5Repeat Steps and 4
INote This procedure should provide the best idle characteristics
while allowing engine idle speeds in gear ranging from 700 to 800 RPM, depending on propeller selection If idle speed is too high, check induction system for air leaks If idle speed is too low when engine condition is correct, decrease idle timing to achieve desired RPM Example: from ATDC to ATDC If idle speed is inconsistent or the engine runs rough or spits lean, refer to Carburetor Mixture Adjustment, Section 2
6Reconnect the temperature switch connectorCam Follower Pickup