View Full Version : what is the proper operating temperature

06-15-2013, 09:34 PM
Sounds stupid. I am reading owners manual, and they indicate proper operating termperature for the maristar is between 170 and 195. Mine always ran around 140. I have been experiencing what i am thinking is over heating. Under load, the temp starts going up, once it reaches 180 to 185, i bring the system down, to idle to cool it off. Am I a freak. Do these things run in the 190's they idle in the 160's. For 10 years I have driven this boat, wake boarded and all around fun, all around 140.... what are your normal opeating temperatures.

06-15-2013, 09:52 PM
I assume you have the TBI motor and not the LT1. There are two thermostats offered for this motor, a 143 and a 160, I have always run a 160 (recommended by a dealer. My temp stays at 160 except when I shut down from a hard run (a little heat soak)

06-16-2013, 08:22 AM
Good time to check impeller may be losing some water flow to cool the motor, also check the inlet at the bottom of the boat, and the inflow screen to the tranny cooler.

06-16-2013, 08:32 AM
On my MCX, temp is 160 degrees (on the gauge) at all times regardless of load or RPM. If yours fluctuates, something's wrong with your cooling system.

140 degrees strikes me a a little cool for optimal fuel system performance on a fuel injected engine.