unable to reach full power

[jabkwab]

Today i finally had the opportunity to work on the airplane again.
the carb sockets where replaced, as well as all the scat ducting.
It certainly is running smoother now without the induction leak, and the carbs required a lot less adjustment to get synchronized!

I did not have the chance to fly it yet, but i do have some results from the test runs.
The problem got a lot less, but unfortunately it is still partly there.

with intermediate throttle settings of up to 4800 rpm everything is running fine. In the lower range rpm drops when applying carb heat,upon approaching 4800 the rpm does not change at all with carb heat.
it is when i apply full throttle, 5000 rpm static, that the revolutions increase with about 150 with carb heat on.

it seems to me that there is not enough fuel flow at wide open throttle, maybe there is a problem with the main jet? It does not look bad or anything. Are they available in multiple sizes?

I am getting quite tired of this problem right now, especially since the flying season in Holland finally kicked of this weekend!

Any help would be greatly appreciated.

Jan

[jabkwab]

Today i managed to makea short test flight, with what i would call results!
The following observations where made:

- on the ground the engine behaves as described in my previous post. That is: a rise in rpm when carb heat is applied at full throttle.

- in flight, regardless of the powersetting, the rpm does not change with application of carb heat.

- max rpm during level flight has risen from 5500 (cold inlet air) / 5800 (hot inlet air) to 6100 rpm, regardless of carb heat valve position.

- max level speed has risen 105 mph, a number i have never seen before on this airplane! (I have only about 50 hours on this one though)

Due to the fact that i can actually overspeed the engine in level flight i think that it would be possible to tweek the propeller a little to achieve a slightly higher cruise speed.


I learned many lessons about Rotax engines during this exercise, and i think that is a very good thing.

Thank you guys for the support, and on to a flying summer!

Jan