High CHT on one cylinder - O-360-A4M
Moderators: Rick, Lance Murray
- Moonshine
- 4 Diamonds Member
- Posts: 355
- Joined: Mon Sep 05, 2011 9:14 pm
- First Name: Max
- Aircraft Type: DA40F
- Aircraft Registration: N727FP
- Airports: KPWK
- Has thanked: 12 times
- Been thanked: 23 times
High CHT on one cylinder - O-360-A4M
Noticed something interesting on my engine data - #1 jug is positively running hot. More evident at higher power settings.
Now, I understand that my -A4M is somewhat different that -M1A's most of you guys have, but would appreciate any suggestions
Here's a good sample of what I'm seeing:
http://www.diamondaviators.net/reports/flights/1800
My ideas so far:
- check the temp rating of the spark plugs, replace them all. I believe Lance said that his airplane originating from the same operator and maintenance facility had a wide array of different plugs.
- check baffling. Didn't see anything weird there, and the fact that #3 is doing fine and #1 is acting up tells me that the chances of this being a baffling issue are pretty slim.
- check for exhaust stack integrity. Seemed fine, but we'll take another look.
- check the CHT probe to make sure it's the same thing as on the other cylinders.. Vaguely remember seeing "replaced CHT probe with serviceable" in the logs.
Now, I understand that my -A4M is somewhat different that -M1A's most of you guys have, but would appreciate any suggestions
Here's a good sample of what I'm seeing:
http://www.diamondaviators.net/reports/flights/1800
My ideas so far:
- check the temp rating of the spark plugs, replace them all. I believe Lance said that his airplane originating from the same operator and maintenance facility had a wide array of different plugs.
- check baffling. Didn't see anything weird there, and the fact that #3 is doing fine and #1 is acting up tells me that the chances of this being a baffling issue are pretty slim.
- check for exhaust stack integrity. Seemed fine, but we'll take another look.
- check the CHT probe to make sure it's the same thing as on the other cylinders.. Vaguely remember seeing "replaced CHT probe with serviceable" in the logs.
- Lance Murray
- 5 Diamonds Member
- Posts: 1163
- Joined: Tue Jul 06, 2010 11:25 pm
- First Name: Lance
- Aircraft Type: DA40
- Airports:
- Has thanked: 7 times
- Been thanked: 120 times
- Moonshine
- 4 Diamonds Member
- Posts: 355
- Joined: Mon Sep 05, 2011 9:14 pm
- First Name: Max
- Aircraft Type: DA40F
- Aircraft Registration: N727FP
- Airports: KPWK
- Has thanked: 12 times
- Been thanked: 23 times
Re: DA40 HID Lights from Lo Presti ...
Thanks, Lance! Was reading that some 10 mins ago - but looks like we are in the wrong thread
- Moonshine
- 4 Diamonds Member
- Posts: 355
- Joined: Mon Sep 05, 2011 9:14 pm
- First Name: Max
- Aircraft Type: DA40F
- Aircraft Registration: N727FP
- Airports: KPWK
- Has thanked: 12 times
- Been thanked: 23 times
Re: High CHT on one cylinder - O-360-A4M
Fascinating stuff
Took the plane to mx, checked the plugs (all good), switched the upper and lower on #1 (didn't do much in the overall EGT picture)...... removed a piece of bubling "fireproofing" paint on the upper cowling that was sitting right on top of the #1.
Runup before
http://www.diamondaviators.net/reports/flights/1803
Runup after
http://www.diamondaviators.net/reports/flights/1804
Need to go fly and see if it did change something - runup temps look better. Go figure.
Took the plane to mx, checked the plugs (all good), switched the upper and lower on #1 (didn't do much in the overall EGT picture)...... removed a piece of bubling "fireproofing" paint on the upper cowling that was sitting right on top of the #1.
Runup before
http://www.diamondaviators.net/reports/flights/1803
Runup after
http://www.diamondaviators.net/reports/flights/1804
Need to go fly and see if it did change something - runup temps look better. Go figure.
- Moonshine
- 4 Diamonds Member
- Posts: 355
- Joined: Mon Sep 05, 2011 9:14 pm
- First Name: Max
- Aircraft Type: DA40F
- Aircraft Registration: N727FP
- Airports: KPWK
- Has thanked: 12 times
- Been thanked: 23 times
Re: High CHT on one cylinder - O-360-A4M
Went flying for a bit today - CHT #1 where it should be.
Took note of some interesting numbers for 40FP - lazy takeoff at 2300lbs - 80' msl, 30.10" baro, +33C and no wind - 2050 feet from start of the roll to positive rate of climb.
Went to do some takeoffs and landings at wet grass strip (fairly tall grass, definitely over 10cm in the book) - 35 Msl, rest the same, managed 1780'.
Came back, quick rest, wanted to go flying again - dead spark plug on #3.
Off to get the M2508 and 3/4" tempest fine wires...
http://www.diamondaviators.net/reports/flights/1809
Took note of some interesting numbers for 40FP - lazy takeoff at 2300lbs - 80' msl, 30.10" baro, +33C and no wind - 2050 feet from start of the roll to positive rate of climb.
Went to do some takeoffs and landings at wet grass strip (fairly tall grass, definitely over 10cm in the book) - 35 Msl, rest the same, managed 1780'.
Came back, quick rest, wanted to go flying again - dead spark plug on #3.
Off to get the M2508 and 3/4" tempest fine wires...
http://www.diamondaviators.net/reports/flights/1809
- Lance Murray
- 5 Diamonds Member
- Posts: 1163
- Joined: Tue Jul 06, 2010 11:25 pm
- First Name: Lance
- Aircraft Type: DA40
- Airports:
- Has thanked: 7 times
- Been thanked: 120 times
Re: High CHT on one cylinder - O-360-A4M
You will like the Fine Wires. I am not sure why the other plugs load up so easily.
- BlackMammoth
- 4 Diamonds Member
- Posts: 318
- Joined: Mon Jun 20, 2011 5:50 pm
- First Name: Phil
- Aircraft Type: DA40
- Aircraft Registration: N29PG
- Airports: KPSP
- Has thanked: 5 times
- Been thanked: 23 times
- Rick
- 5 Diamonds Member
- Posts: 1575
- Joined: Tue Jul 06, 2010 10:09 pm
- First Name: Rick
- Aircraft Type: DA40
- Aircraft Registration: NONE
- Airports: KROA
- Has thanked: 107 times
- Been thanked: 297 times
Re: High CHT on one cylinder - O-360-A4M
Indeed! I went from having fouling issues every other flight (despite aggressive leaning both ground and air) to not a single problem since installing the fine wires. I swear it runs smoother, too!BlackMammoth wrote:Fine wires rock!
Roanoke, VA (KROA)
- Moonshine
- 4 Diamonds Member
- Posts: 355
- Joined: Mon Sep 05, 2011 9:14 pm
- First Name: Max
- Aircraft Type: DA40F
- Aircraft Registration: N727FP
- Airports: KPWK
- Has thanked: 12 times
- Been thanked: 23 times
Re: High CHT on one cylinder - O-360-A4M
Affirmative - fine wires run smoother and allow for peak ops on my O-360