2016 Mercury Pro XS 150 normal idle temp.

[Haynie21T]

I bought a new 2016 Mercury Pro XS serial number 2b230106 a few weeks ago. It sat at he dealers in a box for over a year. When breaking it in I noticed it steaming some at idle. Once on plane it cooled down to 109 degrees. Coming off of plane the temperature goes as high as 165 before coming back down to 151-155. Does anyone know if this falls within normal operating range for this motor? No overheat alarms have gone off yet. I have about 8 hours on motor. Water temp about 84, air temp 85-90. Appreciate anybody else's experience with similar motor. Thanks.

[cowtrimmer]

moved here

[JOE54]

you can see some steam on humid day I would put pump in it just for peace of mind from setting that long personally [cheap insurance]

[Tidewater Bass]

That is too high for a normal operating temp. Take it back to the dealer and have them look over the cooling system. This will be covered under your warranty. The warranty starts when you purchased the motor not the manufacturing date. You should post this in the Mercury Outboard forum.

[SilverFox579]

you can see some steam on humid day I would put pump in it just for peace of mind from setting that long personally [cheap insurance]

Agree with Joe. Take it back to dealer and have them check it. Those idle temps are too high for a new engine IMO. What are your idle and WOT water pressures?

The best place to post is the 2.5L forum (what his engine is).

[Haynie21T]

Thanks for the advice guys. Idle PSI is 1.5-2.0. WOT PSI is 10-12. That's running the motor all the way down on the Jack Plate and trimming to get the bow up. At any throttle setting while on plane the temp stays in 109-112 range. Never had a Yamaha or Suzuki steam after coming off plane unless it needed new water pump. It may have developed a memory while in the box for a year. Going to call the dealer and set up an appointment.

[JOE54]

smart man indeed ^^^^^

[SilverFox579]

Your idle pressure meets spec (1 - 3psi) and WOT pressure should be 12+. On plane temps will vary greatly due to lake water temp, load, speed, etc. Thermostats are out of the circuit once poppet opens. After a while, you'll get to know what's normal for you as you normally use your boat at surface temps you normally run in.

Are your readings from Smartcraft or analog gauges?

[Haynie21T]

Readings are from Smartcraft gauge.

[JOE54]

id still put a pump in it for sure

[SilverFox579]

id still put a pump in it for sure

Me too since WOT pressures are borderline acceptable.