View Full Version : Run Hot after High RPM

07-21-2011, 10:08 AM
My MCX has issues at times running hot. It is never at idle or wakeboarding speed often it is anything over 3500RPM. I have replaced the impeller checked the screen for transmission cooler and probably go for the thermostat next. It is really odd. The only other things I can think of are the that it has a perko flush kit and a strainer in line for the raw water cooling and that could be limiting the flow? an air leak in the flush kit or strainer reducing pressure?Seems unlikely..

Has this happened with anyone else?

07-21-2011, 11:53 AM
Not sure next step, but impellar problem would be opposite. It would over heat at idle. Once up to speed the water pressure on the hull will get enough water to the engine pump to cool and run as long as you need until you slow down back down. This might not fix you now but could get you home one day. Obviously keep an eye on the gauge. Impellar piece might lodge and casue an obstruction.
If your last impellar had several pieces missing, you might check where it could lodge, thermostat, etc. I don't know the MCX. I have heard some boats go from the raw pump to the oil cooler which will catch the pieces before they get to the engine. Neither of my boats have not been that way.