2004 SR Johnson 4 Stroke 9.9-15HP Outboards Service Manual, Page 137Get this manual
POWERHEAD CYLINDERCRANKSHAFTPISTON
Oil SeallO-Ring
Check: Oil seal a-ring Cut, nicked or damagedReplace
THERMOSTAT
Inspect: Thermostat Deposited saltClean Corrosion, wearReplace Check: Operation Thermostat valve operating temperature
5862C (136144F)
If out of specificationReplace
Check step:
Thermometer