Engine will not make power after carb install, post-overhaul

Regarding the jet needle setting, I don’t think that’s going to be the problem. The jet needle is out of play at WOT.  The possible swapping of the enrichment chokes is interesting.  

And Connor, you are an A&P, which is the master certificate.  There is no FAA requirement that you must take the Rotax classes to work on these engines. That being said, I agree that it’s good that you do, and I applaud your adherence to the Rotax training program. 

If this aircraft is an FAA SLSA, "special" or factory built, then if an A&P is going to work on it he must comply to part 65 at the very least.  There are several references to SLSA aircraft and the skill set required and called out by the manufacturer must be followed.  The legal manufacturer of record for the FAA is whomever signed the FAA 8130-15 statement of compliance as part of the airworthiness.  

For the most part OEM will defer to the Rotax manuals for anything related to the engine.  For most A&P they tend to push on and just use the manuals, enforcement from the FAA usually only follows after an incident or complaint.  

In addition this is backed up by part 91. 

§ 91.327 Aircraft having a special airworthiness certificate in the light-sport category: Operating limitations.

(b) No person may operate an aircraft that has a special airworthiness certificate in the light-sport category unless—

(1) The aircraft is maintained by a certificated repairman with a light-sport aircraft maintenance rating, an appropriately rated mechanic, or an appropriately rated repair station in accordance with the applicable provisions of part 43 of this chapter and maintenance and inspection procedures developed by the aircraft manufacturer or a person acceptable to the FAA;

Cheers

Mr. Wizard,

Not to derail the thread but can you explain why an incorrect adjustment of the idle mixture screw (or is it not just for idle?) on the bottom of each carb could result in a reduction in available power at WOT? 
Thanks!

The low speed circuit runs all the time, there is no shut off and therefore it adds to the total mix at WOT.  Plugged, damaged or just badly adjusted it may have an effect.  Admittedly the effect at WOT is small however he is looking for long shots and the last thing worked on was the carburetors.  Why not check them?

Cheers

I have just gone back into the whole thread.  A question was raised about the vent line on the float bowl.  Indeed that is a critical part of the installation.  The vent has to have static air relative to the incoming air for the filters.  it can not be in a high or low pressure zone or run into any long "drain" line.  Anything other than the normal recommended positions from Rotax, such as just under the bale wire or into the airbox (if so equipped) would be recommended.  Given it was already running something odd, as in not Rotax approved, it would be good to check that.  Perhaps pictures would help?  

We have some really smart guys online but they need  a bit more to help. Type of aircraft, hours.  Type of prop and so on.  I for one am unaware of any fixed pitch prop that came on an SLSA without adjustment, perhaps a Prince prop?  They were made in Florida and used on a few Progressive Aerodyne i believe.  (SeaRey amphibian) 

Cheers