I have a Turbo Arrow IV. My number 5 Cylinder CHT has always read lower than the rest. In cruise when the rest run around 320-330 deg F, Number 5 is about 270-280, sometimes even a bit lower. EGT’s on all cylinders are about the same. So I don’t suspect a dead Spark Plug. Mag drops OK too.
HOWEVER I just recently had an annual. Compression test OK etc. Engine gauges as before but now suddenly about 3 hours flying post annual my number 6 Cylinder is showing really low CHT of about 190 deg F. Again no large difference between EGT’s on all cylinders. Mags OK. Aircraft seems to be developing normal power. No vibration or anything.
If I switch the instrument on pre-start up, all cylinders reflect ambient temperature within a few degrees.
It’s been suggested a bad probe – but I have also read that they don’t “half” read. They either work properly or not at all.
Anyone got an idea if I have a potentially big issue here?
One last thing - at the annual I did replace all the baffles
HOWEVER I just recently had an annual. Compression test OK etc. Engine gauges as before but now suddenly about 3 hours flying post annual my number 6 Cylinder is showing really low CHT of about 190 deg F. Again no large difference between EGT’s on all cylinders. Mags OK. Aircraft seems to be developing normal power. No vibration or anything.
If I switch the instrument on pre-start up, all cylinders reflect ambient temperature within a few degrees.
It’s been suggested a bad probe – but I have also read that they don’t “half” read. They either work properly or not at all.
Anyone got an idea if I have a potentially big issue here?
One last thing - at the annual I did replace all the baffles
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