1974 Johnson 135 HP Outboard Motors Service manual, Page 17Get this manual
TROUBLE CHECK CHART (CONT)
TROUBLE
POSSIBLE CAUSE
3LOSS OF POWER (Assuming
Ignition OK) (Cont)
Head gaskets eaking (warped head) (water in cylinde s) 316" diameter hole under heat sensor switch plugged LOWER UNITSee Section Water intakes obstructed Pump housing air bleed estricted
Water passages obstructed
Pump plate not sealing (oottom) Pump Impelle damaged Pump housing worn Pump housing cove seal worn (driveshaCt grooved) Water lube gr omm et damaged LOSS OF POWER ENGINE OVERHEATING
Thermostat damaged
Water passages restricted