power loss in flight

Who did the carb Install?   You, or another person?

Were the Carbs re-synced when re-installed?

It superfically sounds like you are slowly flooding out.

Were new floats installed?

Recheck the Float weights.

The carbs may have been checked 30 ENGINE Hours ago, but the floats sit in the gas for 730 hours a month.

Previous owner had an AnP install and it ran fine for him and great for me for 25 hrs, then yowza.

I am just learning how finicky and high maintenance 912 s are.

Hesitation was quite a shock, like both mags were shut off !!! Then back to full power ???

When you say check float weights, you mean weigh the floats ?  Where does one get a scale to weigh something that small, and how would weight of float cause such a sudden and complete power loss, followed by running fine ?

Most advise it’s clog in tiny carb passage. If floats decompose, why not change them more often ? 
thanks

dan

YES you must weigh the floats!!  Just a couple of grams will make a BIG difference (between floating and sinking).  

You need a scale with precision down to tenths of grams.  These are easily found at certain kinds of shops...

"1 Let the floats dry for 1-2 minutes, then weigh the floats. Only weigh dry floats.

 2 Check the weight of all affected floats using a calibrated scale. Measuring tolerance of the scale: max. 0.1 grams.

 3 The results of the measurement must be documented in the maintenance records. The max. allowable weight (of both floats together) is 7 grams." (MML 12-20-00, p. 35)

Incidentally, Lockwood advises that you weigh floats before sending them carbs for inspection.  By the time a carb gets to them the floats will have been out of the fuel too long for them to get an accurate measurement.

Hi Dani,

The 912 UL or ULS aren't finicky. They run very well and are dependable and the only time there is usually an issue is from  poor installs, aftermarket parts and poor maint. either from lack of or someone does things they shouldn't have. If you have issues then find the cause of the issue and not the result.

I also have a Rans S6S and had a similar problem.
Have a good look at the carburetor vents.
The S6S has air coming in the top through the radiator as well as through the front of the cowling, I think it upsets the airflow around the carbs and causes problems.
I ended up installing a airbox to cure the problem.