1997 Johnson/Evinrude EU 25, 35 HP 3-Cylinder outboards Service Manual, Page 27Get this manual
Break-In Procedure During the first 10 hours of break-in operation you must use 50:1 fueloil ratio in your fuel tank in addition to the operation of the oil mixing unitAfter the 10-hour break-in period, check to see that the oil level in the oil tank has changed, indicating that oil has been used before using unmixed gasoline in the fuel systemIf the oil mixing unit is disconnected, you must use 25: fueloil ratio in the fuel tank for the first 10 hoursTo help ensure long engine life and prevent serious engine damage, using additional oil in the fuel is mandatory during the first few hours of operation of: new engine used engine with new powerhead used engine with newly rebuilt powerhead
INote DO NOT operate motor out of waterWater pump can be damaged or engine can overheatINote DO NOT operate engine at constant throttle settingChange engine RPM often
INote Verify
water pump operation by looking for steady stream of water at the water pump indicatorFirst 10 Minutes Operate engine in gear at fast idle ONLY