wjb
Well Known Member
Hi All,
First engine start last weekend ... and have been poring over the data from the EMS. I found that CHT2 is the black sheep ... about 10% cooler than the other three, though they read the same value at room (hangar) temp.
I've built a jig to test the CHT2 + CHT4 probes against a hot plate, and found that the track fine - both probes read the same temp from the plate up to 350F (where my heat gun rand out of heat) -- doesn't' seem like it follows the sensor.
Given it's a new engine (XIO-360-M1B, Van's standard), I checked the fuel flow at the injectors (Full rich and full throttle, 30" MAP) per the Lyc and Airflow docs. All injectors were putting out the exact amount of fuel (very happy to see BTW)
I'm still curious why this one is the black sheep. Still was that way today while doing some idle circuit adjustments. Test were done in calm air, cowling off. No CHTs were harmed in the process (< 325 F always)
Is this a typical variation, or indicative of some sort of issue? Engine data below.
Thanks!
-Bill
First engine start last weekend ... and have been poring over the data from the EMS. I found that CHT2 is the black sheep ... about 10% cooler than the other three, though they read the same value at room (hangar) temp.
I've built a jig to test the CHT2 + CHT4 probes against a hot plate, and found that the track fine - both probes read the same temp from the plate up to 350F (where my heat gun rand out of heat) -- doesn't' seem like it follows the sensor.
Given it's a new engine (XIO-360-M1B, Van's standard), I checked the fuel flow at the injectors (Full rich and full throttle, 30" MAP) per the Lyc and Airflow docs. All injectors were putting out the exact amount of fuel (very happy to see BTW)
I'm still curious why this one is the black sheep. Still was that way today while doing some idle circuit adjustments. Test were done in calm air, cowling off. No CHTs were harmed in the process (< 325 F always)
Is this a typical variation, or indicative of some sort of issue? Engine data below.
Thanks!
-Bill