Several weeks ago, I posted about my blown powerhead on my '07 225 Optimax. After much convincing from people on this board and Don, I decided to bite the bullet and buy a MercMonitor from Don. Well, on the third trip out with the new powerhead and MercMonitor this past weekend, I got a similar story to what I had been reading about on this board. About halfway through the day, I started her up and started watching the MercMonitor. A minute or two of idling and the temp is still sitting on 98, which I knew from my previous experience the 2 other trips and reading posts here, I had a problem. I decided to go ahead and run the motor but at low RPMs because I was seven to ten miles from the ramp. Temp got to 115 during the run back, but no problems. So back to the shop this week and sure enough thermostat issues. Hopefully no internal damage, I guess time will tell.

They never diagnosed my powerhead failure, but cold seizure sure seems like a more realistic possibility now. I guess that I am going to have to learn how to pull the thermostats because I can't be taking the boat to the shop all the time and I don't see any way to avoid problems. Seems to me like Mercury has a design issue, but I am no expert.

Thanks to Don for talking me into purchasing the MercMonitor. Expensive purchase but definitely a must have guage as far as I am concerned.


Modified by OKDennis at 3:08 PM 10/6/2011