Plagued by engine isses 912ULS
in General Tech Discussion
7 years ago
I have posted about this before and I thought that I was past the issues, but they seem to have started again. At full throttle I occasionally get an engine stumble, this happened again today twice just after take off and led me to abort the flight. This is a brand new mid 2016 build 912 ULS (16 hours)
I have done the following
- taken both carbs completely apart, cleaned with air and carb cleaner
- checked all my fuel lines, at each connection I have run a volume of fuel over time test and I have run several gallons through the lines
- checked my fuel bowls for any contamination several times
- re-synchronized my carbs both mechanically and pneumatically.
The problem had all but disappeared until I experienced it at alititude (9500') on a trip to Payson recently. I confirmed my engine was on the float exchange service bulletin and I swapped all my floats out (one side was 7.7g). But after the float exchange problem seemed to get worse...
As you can see in the image below, when the issue happens its preceeded by the left EGT going 100F hotter than the right (this always happens when you look at the logs).
I also should point out that my static WOT RPM and my climb RPM are pretty much the same, and in climb I seem to lose 50 or so RPM as I climb out, that to me is wrong, but I cant seem to trace any cause and my CHTs and EGTs are cool...
At this stage the only thing I can think of doing is trying to swap out carbs, that it is some strange carb related issue... Can anyone help ? Please :) I have to say this has totally sapped my enjoyment of an otherwise perfect plane.
I have done the following
- taken both carbs completely apart, cleaned with air and carb cleaner
- checked all my fuel lines, at each connection I have run a volume of fuel over time test and I have run several gallons through the lines
- checked my fuel bowls for any contamination several times
- re-synchronized my carbs both mechanically and pneumatically.
The problem had all but disappeared until I experienced it at alititude (9500') on a trip to Payson recently. I confirmed my engine was on the float exchange service bulletin and I swapped all my floats out (one side was 7.7g). But after the float exchange problem seemed to get worse...
As you can see in the image below, when the issue happens its preceeded by the left EGT going 100F hotter than the right (this always happens when you look at the logs).
I also should point out that my static WOT RPM and my climb RPM are pretty much the same, and in climb I seem to lose 50 or so RPM as I climb out, that to me is wrong, but I cant seem to trace any cause and my CHTs and EGTs are cool...
At this stage the only thing I can think of doing is trying to swap out carbs, that it is some strange carb related issue... Can anyone help ? Please :) I have to say this has totally sapped my enjoyment of an otherwise perfect plane.
