This is an infrared thermometer and it is what I consider to be a critical tool for any boat owner. As I always say "tools are free!". What I mean by this is the expense of the tool, and doing the job yourself, is always paid for by the labor savings. In 35 years of tool buying I have yet to find one that was not paid off in one or two projects or uses.


There are lots of things an infrared thermometer can be used for on a boat such as refrigeration trouble shooting, stuffing box trouble shooting, electrical trouble shooting and lots of engine trouble shooting. You can also aim it at the ocean before jumping in to avoid "shrinkage".


So just what is engine temp monitoring and why am I reading this? Well, I wanted to pass along my process and pre-planning assessment for potential future overheating events.


This process actually occurs well before you've had an overheating situation and is the whole premise of this article. It is to get a baseline when your engine is running well.


Essentially, you use an infrared thermometer to measure various marked locations on the engine prior to an overheat so that when you have one you can pull out your notebook or computer, compare measurements, and more quickly isolate and locate the problem.


We'll call this our engine temp baseline. Your engine temp baseline should always be derived from a properly running engine with a clean sea-strainer, clean Heat exchanger (HX), clean exhaust elbow and a new or relatively new impeller. Measurements should only be taken after the engine is 100% warmed up from having been run under load long enough to bring the water heater temp as high as the engine.