Df115 alarms/cutting out and overheating!

[John241168]

Needing some help guys, I am a commercial boat with twin df115's one of the engines today on leaving harbour spluttered a bit then all the warning lights were flashing and then the engine stopped! When I tried to restart it, the alarm noise just kept going and the engine wouldn't turn over! Eventually it turned over after leaving it about 20 mins and I left it ticking over for 10 mins with no probs, when I put it in gear and opened to 3000 revs it was fine for five mind then same again alarms went and engine stopped! Water was coming out pee hole, but the block felt very hot! What do you guys think?

[Harper]

First thing I'd check would be the thermostat. Water out the pee hole is only an indication of a working pump, not of adequate cooling. Thermostat can still be stuck closed and the pee stream will still be strong. All the while, your engine is overheating.

[John241168]

Is the thermostat am easy thing to change on these engines? I am new to outboards as always had diesel inboards before....

[Harper]

No more difficult than any other motor, and probably easier (though I've never done it to my outboard). I say easy, because it pretty much sits right on top of the cylinder head and should be fairly easy to access. Three bolts and a hose clamp. Take it out and put in in a pan of water on the stove, along with a thermometer to check it against. There's a 60 and a 71 degree Celsius available. Don't know which is standard, but I'm guessing that the temp is stamped on the thermostat. You should replace it with the same temp as what you have. If your thermostat checks out okay, let us know, and we'll go from there.