Temp Alarm

[Florida Fisherman]

Alright guys this has got me stumped, I went to leave my house today and decided to run my 2000 Df40 before I left. It started peeing as normal and 1 min later my temp alarm went off I checked the water that was coming from the motor and the water wasn't even warm. What could be causing this thermostat, water pump , or is this a bad sensor in the motor.

[mitch]

The tell tale water comes out before going through engine so it will be cold tell tale water flowing indicates that water pump is working ...............it is most likely that you have a REAL over heat check your t stat.

[Florida Fisherman]

Alright, I just got done replacing the t-stat and for the heck of it I replaced the water pump (which was soon to be due). I fired it up and its peeing like a champ and still the temp alarm sounds on my tach at about a minute after starting. Im guessing there is a temp sensor somewhere thats maybe bad, has anyone had this problem? Mitch thanks for the response.

[boats.net]

Yes the sensor could be malfunctioning.

[deano68]

just went through this with my df40 2007, tested every thing, sensors, engine management system, preesure relief valve, thermostat ect ect..

think you will find as i did, your water galleries around the head will be restricting water flo, due to salt / scum build up.and even though i flushed mine after every salt water use, this still happened...sorry to say but its a costly exersise , power head off, galleries all cleaned out, and full gasket kit...

what i will be doing to prevent this in the future, is flushing the motor for longer so im certain the thermostat has opened, alowing the galleries at the top of the motor to be flushed, and using additive like salt-away, or salt-x with the flush...

deano.