Infrared Thermometer

[maineSS]

I just bought an IR Pro USB infrared thermometer from Thermoworks (www.thermoworks.com/products/ir/ir_pro_usb.html). It seems to have everything I'm looking for- Temp capability over 2000 deg for exhaust work, adjustable emissivity, ability to log multiple measurements, and ability to focus on small areas at longer distances. There's also a USB port for computer download of temp data.

Prices for this capability usually start at $300 plus, but since this unit is new on the market, it's starting at $199, including free FedEx shipping. I was looking for more than the homeowner/hobbyist devices could deliver, and hopefully this unit will prove out. This tool along with the PLX Wideband oxygen sensor should be real helpful in my carb projects. It'll be in next week, I'll have some user impressions then.

[712edf]

I always wanted one of them, to find "dead" cylinders & do other diagnosis. Would come in handy at work when painting certain surfaces in moderate weather.

Bucky

[maineSS]

I shot some areas of the PW engine at idle and at 2000 Rpm- interesting results.

I was interested in exhaust manifold temps of the various cylinders, so I shot #1, #2,3, #4,5, and #6. At idle, #1 was 317 deg, #2,3 was 430 deg, #4,5 was 467 deg, and #6 was 342 deg. Strange that the inner cylinders were hotter than the outer ones! At 2000 Rpm, things evened up a bit- #1 was 542 deg, #2,3 was 551 deg, #4,5 was 632 deg, and #6 was 554 deg. The Thermostat neck was 170 deg, and the exhaust pipe just before the muffler where I located my O2 sensor was 586 deg.

[712edf]

Th outer cylinders being cooler is sort like why people won't the "aisle' seats at the theatre. More breathing room?

Bucky

[maineSS]

On an inline carbureted engine, the end cylinders run leaner than the center ones, so they should be hotter. We'll have to shoot it again and see if the same thing happens.

I also shot the intake manifold in the center and at each ends, these results were more in line with expectations- the center was 141 deg as a result of the hotspot, #1 cyl was 132 deg, #6 was 115 deg @ 2000 rpm. Carb throat was 35.4 deg.

I may try shooting the head at the sparkplug depressions next time to see if the cylinder top temps agree with the exhaust manifold temps.