Cylinder head temperature

[Rusty Pilot]

In my 1974 C model I am seeing my CHT reading at the very low end of green, just over 200 degrees while running around 75 degrees rich of peak.  I was flying in cold air at around 5,000'.  Should I be concerned?  I am only getting the reading off of one cylinder.  I am installing an engine monitor with my current annual inspection. 

TIA.

[David Lloyd]

First flight with an engine monitor will be eye opening. Your CHTs are much more than the low 200s.

[A64Pilot]

1 hour ago, David Lloyd said:

First flight with an engine monitor will be eye opening. Your CHTs are much more than the low 200s.

Maybe, after landing, remove the engine cowling, “shoot” the cyl head with an IR thermometer, compare it with the gauge, preferably at an indicated temp around mid scale on the gauge.

This isn’t extremely accurate of course, but will give you a good idea.

[M20F]

I would echo checking the probe but with the original gauges and probes about the best you can do is fly in the green and not worry.  People did it for decades with no issues and now fret when their CHT average moves by 2 degrees. 

[Shadrach]

27 minutes ago, M20F said:

I would echo checking the probe but with the original gauges and probes about the best you can do is fly in the green and not worry.  People did it for decades with no issues and now fret when their CHT average moves by 2 degrees. 

I started flying in the 90s and to say there were no issues is more than a stretch. Ignorance is only blissful for the pilot. The cylinders still pay price of mishandling. 
 

@Rusty Pilot I don’t have a lot of C time but my limited experience suggests that it is highly unlikely that low 200s is an accurate CHT for the setting given if all systems are operating normally. Test the probe on the ground.

[Rusty Pilot]

22 minutes ago, Shadrach said:

I started flying in the 90s and to say there were no issues is more than a stretch. Ignorance is only blissful for the pilot. The cylinders still pay price of mishandling. 
 

@Rusty Pilot I don’t have a lot of C time but my limited experience suggests that it is highly unlikely that low 200s is an accurate CHT for the setting given if all systems are operating normally. Test the probe on the ground.

Thanks, great feedback.  Hopefully the next time I fly 7104V I will have new probes and engine monitor operating.  

[A64Pilot]

Well I’ve been flying for a bit longer, before engine monitors and intercomms, headsets etc.

There were no more cylinder failures then than now, and I believe the fleet flew more hours then, I’m not saying engine monitors aren’t nice things to have, they are particularly nice for troubleshooting, but the idea of you can’t fly safely without one or you’ll ruin your engine etc is just silly. Operate the thing sensibly or gasp IAW the POH and you’ll be fine.

I’ve had monitors, last one was an MVP-50 and may get another one for this airplane, but not the MVP, too much money and work, but I can fly safely without one until then.

My other airplane doesn’t even have a cyl head temp gauge, didn’t come with one and has flown safely without one since 1946.

I too suspect his gauge is inaccurate, but if it’s real cold he’s not pulling the guts out of it and a little rich it may not be far off, just cruising around LOP with cowl flaps closed mine runs right at the bottom of the green, cooler weather I have to add power to get it into the green good. Climb out it will run 2/3’s in the green somI think it’s as accurate as a 40 yr old non graduated, never calibrated gauge can be.

I believe numbers were left off gauges even EGT intentionally