Max difference between EGTs on CFM563B
 

Can any body tell me if there is still a max difference of 50 degrees celsius between engines 1 and 2 (CFM56 3B2) at idle RPM. I recall that a long time ago Boeing had a maximum limitation of 50 degrees between EGTs at idle RPM.

THANKS

While I'm not aware of a specific limit on ΔEGT, 50° does seem like a lot and Boeing perhaps uses this as a flag to check for the cause.

However, if both engines are otherwise behaving normally, and there's no obvious external cause (e.g. one engine ingesting GPU exhaust, ...) then I wouldn't be concerned.

Check your other parameters as well, i.e FF and N2 speed. these are indicative of a problem that manifests with a TGT increase.

Also bare in mind, which engine is at fault, one could be 25 deg low and other 25 deg high.

Check your cruise TGT and TO TGT.