I need some advice from you engine experts out there:
I'm doing breakin on my brand new Lyc IO-360 with dual P-mags (114 series) and the tach is now 8 hrs 20 mins.
The EGT on cyl # 1 has been 100-200*F higher than the other cylinders from day 1, when leaning on the ground, so I'm wondering why?
(I always lean on the ground, to the point where the engine stumbles and then increase mix until smooth.)
At first I though it was due to the injector not set correct, but that isn't the case I think. I've adjusted it a couple times. At 1000 RPM, the RPM now increases about 30 RPM before dropping.
That schould indicate that the injector is set about right.
On the mag check, all temps are equal (mix is full rich ofcourse) and normal RPM drop.
All EGT's increase the same amount when running on each P-mag separately.
Here's a pic taken on ground:
If I enrichen the mix some, the #1 EGT decreases until it's equal to the other three cylinders.
If I don't enrichen the mix, the #1 CHT gradually increases about 20-50*F.
(Engine runs smooth all the time.)
Therefore SOMETHING causing the #1 cylinder to run hotter than the other three when leaning on ground, but WHAT??
What puzzles me, is that when I'm in the air, the #1 EGT is always equal the the other cylinders.
Here's a pic in the air:
During the first 2-3 hours, #1 CHT was 20-30*F hotter than the other three. The airdam in front of #1 was pretty big, so I made two slots in the airdam. Now #1 CHT is at the same value as the other three cylinders.
For now, I'm flying 75-150*F ROP and I've watched #1 EGT closely when I've leaned to peak and then enrichen to 75-150 ROP. The EGT has always peaked at the same time at at the same level as the other three cyl's. Therefore, I assume this is a ground issue only.
So the big question is: what can cause the EGT on #1 to be so much hotter than the other three when leaning on the ground??
I'm doing breakin on my brand new Lyc IO-360 with dual P-mags (114 series) and the tach is now 8 hrs 20 mins.
The EGT on cyl # 1 has been 100-200*F higher than the other cylinders from day 1, when leaning on the ground, so I'm wondering why?
(I always lean on the ground, to the point where the engine stumbles and then increase mix until smooth.)
At first I though it was due to the injector not set correct, but that isn't the case I think. I've adjusted it a couple times. At 1000 RPM, the RPM now increases about 30 RPM before dropping.
That schould indicate that the injector is set about right.
On the mag check, all temps are equal (mix is full rich ofcourse) and normal RPM drop.
All EGT's increase the same amount when running on each P-mag separately.
Here's a pic taken on ground:
If I enrichen the mix some, the #1 EGT decreases until it's equal to the other three cylinders.
If I don't enrichen the mix, the #1 CHT gradually increases about 20-50*F.
(Engine runs smooth all the time.)
Therefore SOMETHING causing the #1 cylinder to run hotter than the other three when leaning on ground, but WHAT??
What puzzles me, is that when I'm in the air, the #1 EGT is always equal the the other cylinders.
Here's a pic in the air:
During the first 2-3 hours, #1 CHT was 20-30*F hotter than the other three. The airdam in front of #1 was pretty big, so I made two slots in the airdam. Now #1 CHT is at the same value as the other three cylinders.
For now, I'm flying 75-150*F ROP and I've watched #1 EGT closely when I've leaned to peak and then enrichen to 75-150 ROP. The EGT has always peaked at the same time at at the same level as the other three cyl's. Therefore, I assume this is a ground issue only.
So the big question is: what can cause the EGT on #1 to be so much hotter than the other three when leaning on the ground??
Last edited: