MercMonitor Saved Me Already!!!

[OKDennis]

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

[rdc5445]

Definitely agree with "must have guage"! Don installed one for me last year during a service visit. Should be standard with all newer Mercs- IMO.

[DickD]

Yep I cannot understand how Mercury does not require some sort of gauge to monitor temp given the importance of it. Another thing would be good would be to monitor both heads.

[EuropeanAM]

<table width="90%" cellspacing=0 cellpadding=0 align=center><tr><td>Quote, originally posted by DickD &raquo;</td></tr><tr><td class="quote">Another thing would be good would be to monitor both heads. </td></tr></table>

Ah... but you do! The temp figure you're seeing is a "Smart Average" of the temp sensors.... and gives the ENGINE the benefit of the doubt in what it displays.

Avoids confusion for boat operators that wouldn't know Port from Starboard... we must remember that Smartcraft (and these engines) are used on a WIDE ARRAY of boat types (and many average boaters would have no idea what they were looking at other than "it's hot- or it's not").

Regarding thermostat replacement.... there are plans in the works to do some videos this winter to assist in thermostat replacement.

[Lpolk]

I cant think of a more important piece of equipment than the Mercury Monitor. It kept me out of trouble. As to changing or cleaning the thermostats , get you a service manual for your motor, that's a must have with these newer motor. I'm not a wrench turner, I'm a wire twister and I removed and installed my thermostats with the help of a friend. I will say when I had to loosen the fuel rail I got a knot in my drawers , but you will be fine. Handle it with kid gloves. If I would have had any trouble I would have called (Don).