Size jets for Rotax 582

[Jetman]

What size jets do I use for a Rotax 582 Blue Top- 165's or 158's???. Flying in Gauteng 5450 ft ASL on average.

Skin

[Duck Rogers]

What size jets do I use for a Rotax 582 Blue Top- 165's or 158's???. Flying in Gauteng 5450 ft ASL on average.

Skin

I'm comfortable with 158 at the Highveld.
However, the last time I gave that advice to someone, I was taken to task by his AP who refused to sign the plane out unless it had 165's in.
Rotax manual says 165 at the coast and to be "adjusted" for altitude. According to the conversion chart it works out to 158 at Reef altitude, so that settles it for me.
By the way, the air jets in older Solex automotive carburettors use the same jets as the Bing main jet you have in your 582. If Comet Aviation don't stock them, try to find 160 air jets for a Solex and stick them in the Bing if you're uncomfortable with 158's.

[Jetman]

Thanks Duck

The same thing happened to me as mentioned above. The one AP suggested 158's and the other nearly made a back flip after hearing that. Personally I'm using 165's for years and yes, ...165's.... here we go again.

Skin

[Miskiet]

The reason AP's specify the richer jets for highveld use is it makes the engine (and more importantly) the pistons run cooler. Two strokes are fuel-cooled. It also eliminates engine outs when flying to the lowveld if you've forgotton your lean jets in. The engine is thirstier on 165's - If you want to run optimal fuel ratio's, you need a very good EGT guage (digital one like MGL, steam guages are not accurate enough) to make sure you manage temps properly. There used to be a very good 4-part article on here somewhere about carb tuning. Very worthwhile to read it.

[John.com]

Off the web . . . . Bing 54 Main Jet Correction Chart!

Cheers, John

[John.com]

Here is a link to a "Bing 54 Carburetor Guide"

http://www.ultralightnews.ca/bing/bingcarbtuning.html