2010 Mercury 40hp 4-stroke

[Trickle56]

So buddy and I planned on doing a little night fishin tonight but we've ran into a problem. My buddy took his boat out last night and ran kinda shallow into a sand bar. On his way back to the landing his temp warning went off with a dribble out of the tell tale. Safe to say he sucked up some trash. He flushed it last night and It ran fine on muffs and stream was normal. So now we just took it out and it's peeing good but temp warning keeps going off. So if after flushing it could it still leave a clogged passage way? Or is there another culprit? Thanks for any input?

 

[Silvertip]

Re: 2010 Mercury 40hp 4-stroke

What did he back flush and how?

 

[Trickle56]

Re: 2010 Mercury 40hp 4-stroke

On the back of this motor is an adapter that a garden hose can screw into. Since my last post we played around with it on the water we can run half throttle for quite awhile before it gives us the warning horn. If we start from a cold start and take of full throttle it gives the warning within a minute. So I'm thinkin it's a thermostat. Y'all think that's is Safe to say or should I take the troubleshooting process farther?

 

[Timestep]

Re: 2010 Mercury 40hp 4-stroke

It wouldn't do any harm to take the thermostat out and check it in a pan of boiling /hot water? Also looking inside where the thermostat is might give a clue?

Dave