[rwilmac]

The overheat alarm on my 1995 Yamaha 115 is going off. I replaced the water pump and both heat sensors . It is peeing strong and doesn't feel excessively hot but the alarm goes off after running on plane a couple minutes. I ran it in the boat slip for 5 min. and the alarm never sounded, it peed good and water was not hot. I need some suggestions, please. Thanks.

[ianyoung77]

I would check out the thermostat. If it's not full of gunk check the operating temperature

[rwilmac]

Thanks, I'll try that. A friend also suggested backing down kinda hard in reverse to dislodge any grass that might be hung up.
Could that be it ?
Thanks for your help?

[Ray Neudecker]

Also check the poppit valve at the rear of the motor. Be careful not to shove the grommet into the block while checking or cleaning.

[pine island fred]

Check my post YAMAHA OVERHEAT FIX post on 11 NOV. Just might be the problem. FRED

[rodbolt]

first ya gotta determine is it an actual overheat or is it an oil alarm.
if its a precision blend model and the oil filter at the remote tank is clogged it will run a few minutes then trigger the alarm as the engine can use oil faster than it can be transfered if the filter is clogged.
use a temp gun to find the actual temp of the motor.
with a strong stream at low speed and no low speed overheats I would not suspect the poppit valve at all but it does need routine maint .
worst case is pull the heads and covers and clean the salt scale off of everything.