[dbhill916]

Hi folks,

Just a curious question: Does anyone have the backstory regarding why the choke disc valves (I know, it's not really a choke, it's an enrichment circuit) are labeled "R" on the left side and "L" on the right side of the engine?

Heavy Maintenance Manual §73-00-00 p 33: "The shafts for the rotary disc valve have two markings, L and R. The shaft marked R is for the carburetors for cylinders 2/4, the shaft marked L for the the carburetor for cylinders 1/3. Fig. 73-25 shows the positions of the markings on the choke shaft."

thanks in advance,
-dbh

 

[RFSchaller]

A few years ago I had a west coast shop do the 500 hr overhaul of my carbs. They swapped Right to Left resulting in an engine that would not start. After much troubleshooting I figured it out and swapped the “choke” assemblies back. The engine sprang to life. Right and Left are labeled for a reason.

 

[R100RS]

R vs L

I don't know the backstory. But I do know that Bing carbs are used for more than just Rotax 912 engines. So, maybe another application...?

 

[NinerBikes]

I seem to recall something about the engine's original design being a "pusher" motor, whereas on the RV-12, it is in a "tractor" configuration.

So, when Rotax 912 first came out, that's how the Bing carb enrichement levers got labeled.

 

[dbhill916]

I seem to recall something about the engine's original design being a "pusher" motor, whereas on the RV-12, it is in a "tractor" configuration.

So, when Rotax 912 first came out, that's how the Bing carb enrichement levers got labeled.

Using Occam's razor: that sounds like the simplest (and thus best) explanation. I'll take it!

 

[NinerBikes]

Rotax should have the BING carburetor MFG label the enrichment stuff "Cyl 1 3" and "Cyl 2 4" to solve this problem.