I bought a 92' checkmate 251 convincor on friday. On the test drive everything went well temp, oil pressure, motor is very strong. The motor is a 540 with what I believe to be eddie marine crossover. Well today we put in in portsheldon and ran down to holland, about a 9 mile run. On the way down I noticed that the temp jumped to 200 in about 2 sec. so I backed off and temp started dropping. Took off again no issues the whole trip down. On the way back up it happened like 6 times, then it also started doing it at about 1000 rpm. It would rise to about 200 and then start slowly dropping again. We were cruising at about 3200-3400rpm so I was not roding on it.

When i got home I pulled the thermostat and it only has one small hole. Could that be the issue?

Also boat has a 26p ballistic 3 blade and blows out all the time. Anyone have a similar set up that could point me in the direction of a new prop? I am thinking a 26 hydramotive 4 blade???

From what I have found on here looks like they are a PITA but do you think I should run with out a stat or eliminate the crossover. Also it would pe a huge pain to remove front of the motor is basically under the back seat.

Congrats on the new boat. If your loud, stay out of Holland. I just got a ticket friday night. Run it without the thermostat and see if it still gets hot. If it does you either have a blockage or a bad impeller that cant keep up with water flow at high rpm. Bravo drive?

sounds like the thermostat, run a 140, drill 4-6 1/8 holes in it..also make sure impellor is good..just sold one of those boats..loved it...would try a 26 bravo 1, good all around prop, a mirage plus is a little faster on top end if looking for all out top end..not as smooth and mid range suffers a little to

Thanks for the replys. It is a bravo 1 drive. I boat mainly out of holland it is loud but I have passed the cops 2 or 3 times out there already, they just wave. I think that because your boat is awesome they were hoping you would just pay the fine and they meet their quota.

EZ what kind of power did your 251 have? There is a bravo 1 26 in holland that I might pick up tomorrow. I am also going to get a new thermistat, drill the holes and we will start there.

Just had similar problem, check and make sure impeller is good, check all hose and clamps make sure they are tight after de-winterizing. Mine was a loose hose clamp on suction side of impeller and temperature was fluctuating.