Home › Forum › Ask A Member › 9.5 Johnson Temperature › Reply To: 9.5 Johnson Temperature
Like Frank says, thermostat operation would be near impossible to judge from the cooling water outlet on this engine. I would be more suspect of a worn impeller/housing if the outlet water volume seems to drop after start up. Grooved/pitted impeller housings are often overlooked as a source of poor water pump performance.
Have you had the gearcase off lately? I only ask because these engines are low in the water and more prone to spline seizure, especially in salt water. So, be very careful if you are removing the gearcase for the first time. Forcing the gearcase down/off, while leaving the driveshaft stuck in the crank splines creates quite a mess.