Re: Newbie Boater with 200hp Johnson
t-stat = thermostat...tells you the temperature that the engine is running at or the temp of the water that is cooling the motor(same thing), if the motor overheats you'll see it on the temp guage so you can shut her down before you do damage!! If the t-stat is broken then the gauge will not work and you will just keep running it not knowing that its overheating, eventually it will bog down and stall (VERY BAD)
Yes you should change the impellar, its probably not very good if he hasnt changed it in a long time. If you do get it started, check to make sure water is coming out of the pee hole.(this means water pump and impellar are working).
Hope this helps!! good luck.
The thermostat contols the engine temperature.....it does not tell you what that temperature is or mean that there is a temp gauge present. In essense it keeps the engine from running cool, as it will only open when the water reaches a certain temperature.
The reason for replacing this is that they can become stuck closed and then the engine wont cool properly.
If water is coming out of the pee hole, that only means that the pump is moving water.......it doesnt mean it is working properly. The impeller itself can dry rot over time and wears out with use. If it were to come apart when the motor is running it would block cooling passages and overheat the motor. It should be replaced no matter what if it hasnt been already.
I would buy a manual before I did much else. It will give very specific wiring diagrams and the such (get a factory service manual....often on ebay for 10-$15.)
Also I would check compression. If it is bad (less than 100psi or 10%+ variation between cylinders) then you will have to pull the head. You may not what to waste time or funds on the motor if this is the case.
Really it would be a good idea to read "awakening a sleeping outboard" in the FAQ section.
