I think i may know what that other user may have been refering to......it's been a while.. maybee 10ys or more. but at one point someone was importing a repop 241 style carb that was indeed some sort of light alloy. it usually corrodes with a white powder and has a gold colored finish that flakes off in pieces leaving a porous white powder underneath. weighs about half a cast carb.
in my shop I have a 241 and 33 original, a tractor supply cast iron repop no name, and one of them alloy ones.
same kit from tisco seems to fit all of them... but that flaky one with powder residue is odd. I've never used it.. always held it in reserve.. payed 35$ for it... probably got ripped.. dunno.
my guess is it is zinc-aluminum alloy based on some materials we use at work that are zinc-aluminum allow.
It is not straight cast aluminum for sure. I have other cast aluminum parts and it is different.
that plating is the troubling part. it is plated internally.. and flakes internally too. pieces the size of yur fingernail will sometimes come up with a white bubbly corrosion under it.
i have often wondered if it was zinc nickle plating...
anyone else see these carbs?
Note. I have not seen one of these carbs in a decade ( since I got mine anyway ).... I have bought a few of the cheap cast iron ones from tractor supply for small engine projects at work.. and for the most part those are fine.
I wonder if the other user who posted earlier maybee ran across one of these carbs?
If someone knew of a quick / easy home test to find out what it was I'd be interested..
any home chemists out there?