High temp CHT

aussieflyer1 · #1 02-09-2013, 03:08 PM

Any help on a high CHT which I have posted here before. I replaced my #2 cht last week with a Westech 713-7DK "j" taxi around and it seemed to hold well with the other three cht's.
Today when I went flying all CHT's read 350 degree range except the #2 at 703 degrees. Before you tell me that's hot I know, my oil temp and PSI were all normal, EGT in the 1100 range hottest 1200. Could a new Westach CHT go bad that quickly or can someone suggest what I should look at. I'm thinking of putting #2 into #4 and see what it reads.
Thanks for any help.
aussieflyer654@gmail.com

Greg Arehart · #2 02-09-2013, 03:20 PM

Yes, I would swap the probes and see if you get normal reading on that cylinder. If the high T follows the probe to another cylinder, it is the probe. If it doesn't, it must be the cylinder. I suspect the probe is either bad or the wrong thermocouple type - hard to imagine a cylinder that hot with fairly uniform/normal EGTs.

Greg

BobTurner · #3 02-09-2013, 03:44 PM

A look at ACS shows some CHT units use type J, some type K. They are not interchangeable. What are your others? Either you've got the wrong type or it's defective.

Morpheus122 · #4 02-09-2013, 04:02 PM

Could it also be a factor of the location of where the probes were installed?

Also, could it be a factor of where the cylinder is located? Is it natural for the rear cylinders to run hot due to air flow differences. Maybe the other one is hot too and the probe is in a different place?

There may be other variables to consider.

By the way, this is the classifieds section.

aussieflyer1 · #5 02-09-2013, 07:12 PM

Thanks, my EGT's are "K" clamp style, they are labeled. I have the Bayonet CHT's I will have to find the Westach "K" style and see if this is the correct thermocoupler.
Thanks for your help.

phapp · #6 02-10-2013, 05:21 AM

Mike Busch's article in the current issue (February 2013) of "Sport Aviation" discusses CHT's.
Actually it's about cylinder head separation, but he gives some good temp information.

MauiLvrs · #7 02-10-2013, 08:51 AM

Quote:

Originally Posted by aussieflyer1

...
Today when I went flying all CHT's read 350 degree range except the #2 at 703 degrees.

If it was really 702 ... it would be over ... It's 200 deg over max