Why is motor still running hot????

[tprice]

I just replaced the impeller in my 99 225 suzuki. Before I replaced it the temp warining buzzer/light would only go off if i trolled for more than about 10min at min speed(with boat just pushed into gear and nothing else). As soon as i sped up a little the light/buzzer would quit. There was always water flow and I never had any other problems at other speeds. <br />Well I suspected the impeller since It had not been changed in a while. I changed the impeller with a lot of help from this and another forum.<br />I took the boat out Sunday AM and begin trolling for freshwater stripers. Well all seemed fine. WE trolled at the min speed for about 3 hours, no fish, and all of a sudden the light/buzzer went off again. Well we turned the motor off and rolled in the lines and put everything away. I then started the engine and everything was fine. Since we were about 10 miles from the landing I ran at various speeds, anywhere from fast troll to WOT and no more pr0blems. When we got back to the landing we dropped back to min speed and after about 5 min the light/buzzer came back on.<br />I am stumped as to what is causing this. The boat does not have a temp guage and I also checked for any obstructions.<br />Any other ideas or should I just save the time and effort and take it to a Suzuki Mech.<br />I am also going to have a temp gauge installed also.

 

[lakensea]

Re: Why is motor still running hot????

The temp alarm will also go off if the temp rises too quickly - long before it actually overheats. If you restart the engine right away and the alarm is not going off, then it's a gradient alarm. Did you replace just the impeller or the wear plate & gasket also? Look for a possible bad seal between the wearplate and gear housing.. You also have a secondary water pickup and you may have a bad seal where the tube enters the water pump. Also check t-stat and pressure relief valve.

 

[jim dozier]

Re: Why is motor still running hot????

Although they are not cheap, the temp sensors have been known to be faulty. You might try purchasing one of the new laser pointer/infra red temp monitors which I have read are available at Radio Shack to verify the temp when the sensor kicks on. If its out of spec then you can buy a new sensor. As mentioned above check your thermstat. If it is sticking closed or only opening part way it may be causing trouble. When you replaced the impeller, what was the condition of the impeller housing? Were there any grooves in it?

 

[tprice]

Re: Why is motor still running hot????

Thanks for the ideas, I did replace the impeller, housing and gasket.(it all came in the kit). I also scraped the old gasket off to make sure I had a clean seat for the new gasket.

 

[vidar]

Re: Why is motor still running hot????

check if you have a waterflow sensor..it may give prob also..