proper diagnosing procedures

[brother chris]

I just replaced my water pump on my 1978 55hp Evinrude. <br />Before I changed it, the overheating alarm would go on if I let the motor sit idling for more than 5 minutes....so that is why I changed the impellor.<br />Now that i have changed the impellor, I let the motor run for just over 5 minutes and the same thing happened. The over heating alarm went off. <br />I know there is only a couple reasons this could happen...so next question..should I change the thermostat?<br />Like I mentioned in earlier posts, I have misplaced my manual and have not found it. I am not going to go and buy another(I will find it in time), so I would appreciate any help anyone could give me. <br />Thanks,<br />B.C.

 

[Dhadley]

Re: proper diagnosing procedures

Did you change just the impeller or the plates too? Changing the t-stat cannot hurt. It'll give you a chance to look at the pressure relief valves.

 

[Solittle]

Re: proper diagnosing procedures

Yep it is time to do the thermostat. You might also pull the head, clean out any crud in the water passages and replace the deflectors.

 

[DHPMARINE]

Re: proper diagnosing procedures

The thermostat is the next logical place to go,but if you can get a wax stick or another way of measuring the actual temp,you may not be overheating,and only need a new temp sensor.Or have a false warning horn.<br /><br />DHP

 

[brother chris]

Re: proper diagnosing procedures

thanks guys. I will go and get a wax stick to see if it is actually overheating. <br />But it cannot hurt to replace the thermostat...it does not take that long to do that. Think I will do that too. <br />I appreciate the info....thanks fellas