1968 Evinrude Big Twin, Big Twin Electric, Lark 40 HP Outboards Service Manual, Page 46Get this manual
fIf motor is manual shift model, remove shifter lock spring and shifter lockexhaust coverRemove four nuts gRemove and four screws attaching power head to exhaust housing assemblySee Figures 5-8 and 5-9Lift power head to disengage driveshaft splines and place bench for disassembly hThe from the crankcase
main bearing seal removed bearing without disassembling the using seal (Special Tool #379239)
Figure 5-7Checking Motor Temperature
Two Thermomelt Stiks necessary to check motor 125 Stik and 163 StikWith the motor at operating temperature, the 125 mark should melt and the 163 mark should not melt
If the 125 mark does not melt after reasonable length of time, the thermostat is stuck and the motor is running too co1dIf the 163 mark also melts, the cooling system is not functioning properly, algWing the motor to overheatCheck for worn assembly, leaky water system, restrictions in the cooling system
Figure 5-8Power Head Attaching Nuts