Flying_Monkey
Well-Known Member
- Joined
- Sep 22, 2014
- Messages
- 3,041
- Reaction score
- 1,440
Hi all, I have a PA32 with IO540-k1A5. I have a JPI EDM 930 certified engine monitor as primary. I've flown this plane about 650 hours with this monitor. I am usually able to fly around 9500 or 10500 feet and lean to peak or just slightly lean of peak and burn 12.1-12.4 gph for 140KTAS. It's been very consistent and I even set the engine monitor after leaning to monitor the hottest EGT which is #1 that sits around 1530.
The JPI will actually make the EGT bar graph yellow above 1550.
I realize absolute EGT values don't really mean anything. I'm pretty up to speed on all the articles about leaning (pelicans perch and mike bush et al.)
On Sept 23 I flew L.A. to Reno at mostly 9500 and 10500 feet. Leaned as usual. Everything looked great and as expected. EGT#1 peaked out around 1550 and I could lean to 12 gph with EGTs behaving and not in the yellow.
2 days later Sept 25 the reverse route at 10500 and I wasn't able to get lean of peak at all. The EGTs just kept rising and rising. EGT #6 kept getting into the HIGH 1600s which I have never seen before. And the others kept rising as well even when leaning down below 11 gph and losing a lot of power. The JPI even started showing #6 EGT as RED which I have never seen before. But it looked like all the EGTs were doing the same thing- EGT #1 usually peaks around 1550..but it kept going up to over 1600. Ive just never seen all the EGTs turn yellow while leaning no matter what I do at those altitudes. So...SOMETHING must be different.
I ended up enriching the mixture to 14-15 gph and the plane flew fine with CHTs in the low 300s and 137-142 KTAS depending on the turbulence etc.
I'm attaching screenshots of the engine monitor data and links to the data...
SEPT 23 - https://apps.savvyaviation.com/flights/shared/flight/8694390/8d7dfb3a-4141-4c76-8a67-119fb5beded6
SEPT 25 - EGT weirdness - https://apps.savvyaviation.com/flights/shared/flight/8694391/2c56f92f-9437-440e-bb60-07d127ad76f6
Any ideas on where to start would be helpful. Mags? Plugs? Something with ignition?
Eric
The JPI will actually make the EGT bar graph yellow above 1550.
I realize absolute EGT values don't really mean anything. I'm pretty up to speed on all the articles about leaning (pelicans perch and mike bush et al.)
On Sept 23 I flew L.A. to Reno at mostly 9500 and 10500 feet. Leaned as usual. Everything looked great and as expected. EGT#1 peaked out around 1550 and I could lean to 12 gph with EGTs behaving and not in the yellow.
2 days later Sept 25 the reverse route at 10500 and I wasn't able to get lean of peak at all. The EGTs just kept rising and rising. EGT #6 kept getting into the HIGH 1600s which I have never seen before. And the others kept rising as well even when leaning down below 11 gph and losing a lot of power. The JPI even started showing #6 EGT as RED which I have never seen before. But it looked like all the EGTs were doing the same thing- EGT #1 usually peaks around 1550..but it kept going up to over 1600. Ive just never seen all the EGTs turn yellow while leaning no matter what I do at those altitudes. So...SOMETHING must be different.
I ended up enriching the mixture to 14-15 gph and the plane flew fine with CHTs in the low 300s and 137-142 KTAS depending on the turbulence etc.
I'm attaching screenshots of the engine monitor data and links to the data...
SEPT 23 - https://apps.savvyaviation.com/flights/shared/flight/8694390/8d7dfb3a-4141-4c76-8a67-119fb5beded6
SEPT 25 - EGT weirdness - https://apps.savvyaviation.com/flights/shared/flight/8694391/2c56f92f-9437-440e-bb60-07d127ad76f6
Any ideas on where to start would be helpful. Mags? Plugs? Something with ignition?
Eric
