155 IMT high temp alarm

[Zundels]

Well, looks like it could be my turn for a new sensor or repair on a loose wire.

Got out on the water today and had engine warmed up. Then the SmartCraft alarm goes off with 155 IMT HIGH. The SmartCraft showed the Intake temperature climbed to 205 degrees and the manual says that is the top operating temp.

Checked all systems and they were normal:
-Raw water intake valve is open, filling the raw water filter, water is moving and the filter is clear, bowl is full of water
-Exhaust has water coming out at a steady flow
-The closed system antifreeze coolant checks out at normal ranges with two different tests
-The engine temperature stayed in the normal range the entire time (178 degrees or less)
-No fluids in bilge, everything is sealed and normal.

-After the engine was cool, hooked up the fresh water rinse hose and flushed out the salt water. The engine temperature was cool at 75 degrees. The SmartCraft intake temp after hours of being shut down, showed 203 degrees on a cold engine at 75 degrees and stayed at 203 until we shut it down a few minutes later. Will try again tomorrow after a night of cool down.

155 IMT HIGH fault code says "Intake Manifold 1 Temperature - Data Valid but Above Normal Operational Range-Most severe level.

Might the sensor be an issue? Or a bad wire connection. What else should we be looking at? If it is a sensor, would this be a sensor the Cummins NW mechanic may need to replace? Anyone else replaced this sensor?

I see there are two previous threads on this topic:

viewtopic.php?f=6&t=1989&p=14200&hilit=155+IMT+High#p14200

viewtopic.php?f=5&t=1298&start=0&hilit=155+IMT+High

Thanks, Don

 

[sidetrack]

I have been going thru the same issue right now. Unfortunately the sensor is on back-order and Cummins NW is sending me one once it arrives on their shelf. The original contact that got the ball rolling was Pat McCullough: 425-204-5590. My sensor was set off when a piece of the internal motor zinc broke off and jammed and screwed up the raw water pump impellor. Once the sensor went off it was screwed and goes off on a regular basis now. I just mute it and keep on running. Good luck.

 

[bbrh842]

A local boat had exactly the same issue one month ago, and resolved it by replacing the sensor.

 

[sparky]

Another $125 sensor. We had that problem two summers ago. I have lost track how many of our boats have had to get that part replaced....

Monika

 

[Zundels]

Spoke with Cummins NW Anchorage, AK today and they could be looking at our 2009 R-25 Cummins 150 early in the week. Checking out the 155 IMT HIGH alarm, I did start the engine cold and the intake temperature immediately showed 205 degrees and the alarm sounded. Pressed the check to silence the alarm and this confirmed our earlier thoughts. So, we are thinking that it is the wiring or the sensor. Will know more soon once the mechanic arrives and will post results to the site.