1969 Evinrude 40 HP Big Twin, Big Twin Electric Lark Service Manual 4596, Page 46Get this manual
fIf motor is manual shift model, remove shifter lock spring and shifter lock gRemove rear exhaust coverRemove four nuts and four screws attaching power head to exhaust housing assemblySee Figures 5-8 and 5-9Lift power head to disengage driveshaft splines and place on bench for disassemblyhThe upper main bearing seal can be removed from the upper bearing without disassembling the crankcase by using seal puller (Special Tool #379239)
Figure 5-7Checking Motor Temperature
Two Thermomelt Stiks are necessary to check motor125 Stik and 163 StikWith the motor at operating temperature, the 125 mark should melt and the 163 mark should not melt0 0
mark does not melt after reasonable length of time, the thermostat is stuck open and the motor is running too coldIf the 163 mark also melts, the cooling system is not functioning properly, allowing the motor to overheatCheck for worn pump assembly, leaky water system, or restrictions in the cooling system
If the 125
Figure 5-8Power Head Attaching Nuts