[rv9aviator]

I have never had a plane with more than one EGT probe. Now I have all four and I have no idea if this is normal or if I have a probe or EMS problem. When Idling and taxiing the EGT's are higher on the front 2 cylinders by 150 deg. When in cruise the EGT's are higher on the rear 2 cylinders by 150 degrees. The engine is an 0320-E3D fixed pitch RV9A. The readings run from 1300 to 1450 in both situations. The CHT's are pretty even across the board in cruise and on the ground. The engine is running perfectly. This is a simple mag and carb engine. Any thoughts?

 

[airguy]

I have never had a plane with more than one EGT probe. Now I have all four and I have no idea if this is normal or if I have a probe or EMS problem. When Idling and taxiing the EGT's are higher on the front 2 cylinders by 150 deg. When in cruise the EGT's are higher on the rear 2 cylinders by 150 degrees. The engine is an 0320-E3D fixed pitch RV9A. The readings run from 1300 to 1450 in both situations. The CHT's are pretty even across the board in cruise and on the ground. The engine is running perfectly. This is a simple mag and carb engine. Any thoughts?

Sounds like different mixture distribution in the manifold at different manifold pressures - not really surprising with a carbureted engine.

 

[Bluebeard]

What happens when you apply simultaneously carb heat and leaning?

 

[Ironflight]

Are all four of your EGT sensors the exact same distance from the exhaust flange on the cylinder? Even a tiny difference in distance will cause a temperature difference - first thing to confirm.

 

[rv9aviator]

Paul, what would be a tiny difference? Are we talking a 16th of an inch or maybe 1/8 of an inch making a difference. The next time I fly I will check the leaning and carb heat to see what difference it makes. Thanks!

 

[agough277]

Sounds like too much info. If it runs fine don't worry. None of the instruments used are calibrated.