Value of EGT measurement on 912 ULS?
in 912 / 914 Technical Questions
10 years ago
We've had two differing opinions, from experienced Rotax users, on whether it's worth measuring EGT on our 912 ULS on a self-build a/c (via an EMS system):
Against:
1) ....to be sensibly meaningful,all 4 exhaust tracts need to be monitored,and you will have to provide 4 suitable senders and bore the necessary fitting holes in the exhaust headers, which will necessitate removing the already fitted headers. On this one, my advice is not to go there, as on a 4-stroke engine of the Rotax type they have very limited value in the information displayed and few owners (UK) ever fit them.
For:
2) There are 2 very good reasons to fit the EGT sensors. If you have any fuel system problems, the first signs will show up immediately in increased EGT readings. I know you have a fuel pressure gauge, but you could get a blockage at the carb fuel intake, or a float problem and no indications would show up on the pressure gauge. Secondly, if the carbs go out of balance, this will show up on the EGTs.
We'd very much appreciate further opinions, particularly on the advantage of measuring EGTs.
Against:
1) ....to be sensibly meaningful,all 4 exhaust tracts need to be monitored,and you will have to provide 4 suitable senders and bore the necessary fitting holes in the exhaust headers, which will necessitate removing the already fitted headers. On this one, my advice is not to go there, as on a 4-stroke engine of the Rotax type they have very limited value in the information displayed and few owners (UK) ever fit them.
For:
2) There are 2 very good reasons to fit the EGT sensors. If you have any fuel system problems, the first signs will show up immediately in increased EGT readings. I know you have a fuel pressure gauge, but you could get a blockage at the carb fuel intake, or a float problem and no indications would show up on the pressure gauge. Secondly, if the carbs go out of balance, this will show up on the EGTs.
We'd very much appreciate further opinions, particularly on the advantage of measuring EGTs.
