IR readings

[wshelton]

I have a pair of DD 671s N that I was curious if it would be an accurate reading of the engine tempertures if you shoot the sending units on the engine with a IR temperature guage. I did thiis the other day. Shot each engine at about the same distance on the top of the sending unit where the wire attaches. The engines were at running temperatures after a hard run, however at idle when the readings were done. The gauges at the helm read 175 ,the shot was at 140 while he other gauge was at 185 and the shot reading was 160. I do not trust the guages, however know the engine alarms are good to go should an overheat occur. Any other ideas?

[Pascal]

there are a number of things that can affect the accuracy of an IRTemp reading including reflectivity of the surface, distance, etc...

Mike recently mentioned someone who spent thousands chasing a non existent problem...

that said, ive found mine to be very accurate and a great troubleshooting tool. When i take a reading I try to get the highest temp by moving the pointer around a little. this seems to eliminate errors.... ex when taking a reading off a thermostat housing, i look for the highest possible number. usually that works pretty well.

try that, a 20 deg difference between engines is significant.