I would like to add a EGT and maybe also a CHT to my O-300-C.
What cylinder should the probe go on?
Does it matter?
What Cylinder to probe for CHT/EGT
Moderators: GAHorn, Karl Towle, Bruce Fenstermacher
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jrenwick
- Posts: 2045
- Joined: Thu Apr 01, 2004 8:34 pm
Re: What Cylinder to probe for CHT/EGT
I believe you want CHT on the hottest cylinder, and EGT on the one that peaks first during leaning.
My O-300 has EGT and CHT on all cylinders. I observe that #2 cylinder is always the hottest, and I think that's generally expected.
When leaning, I believe it's #5 EGT that peaks first (although it's been a long time since I've tried to use peak EGT for leaning, and my memory may be faulty). I've gone back to leaning by the method described in the owner's manual, and using EGT and fuel flow just for fine-tuning.
Others may weigh in with what they see, and then you can decide.
My O-300 has EGT and CHT on all cylinders. I observe that #2 cylinder is always the hottest, and I think that's generally expected.
When leaning, I believe it's #5 EGT that peaks first (although it's been a long time since I've tried to use peak EGT for leaning, and my memory may be faulty). I've gone back to leaning by the method described in the owner's manual, and using EGT and fuel flow just for fine-tuning.
Others may weigh in with what they see, and then you can decide.
John Renwick
Minneapolis, MN
Former owner, '55 C-170B, N4401B
'42 J-3 Cub, N62088
'50 Swift GC-1B, N2431B, Oshkosh 2009 Outstanding Swift Award, 2016 Best Continuously Maintained Swift
Minneapolis, MN
Former owner, '55 C-170B, N4401B
'42 J-3 Cub, N62088
'50 Swift GC-1B, N2431B, Oshkosh 2009 Outstanding Swift Award, 2016 Best Continuously Maintained Swift
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GAHorn
- Posts: 21302
- Joined: Fri Apr 12, 2002 8:45 pm
Re: What Cylinder to probe for CHT/EGT
The NO. 2 cylinder is the one chosen by Cessna for both probes.
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons.
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons.
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