Carb Low Down for the Norvel
 

Heres some pics of the carb versions you want, these are both early engines with and air bleed idle ajustment the first is a 049 or 0.8 the second is 061 or 1.0 these are being converted to revlites one, BM the other an AME I get these off of ebay all the time and convert them and then sell the swapped engines or experiment with the early liners and pistons, these versions will idle down very well the 1.0 has a round carb with the air hole on top the 0.8 is a sq. carb with the air bleed hole in the carb body venture, you can see the air bleed screw in the back of both carbs behind the needle valve

061
 

this is the best round carb

Carb Low Down for the Norvel
 

That's not a idle screw, it's a throttle stop screw, isn't it?

Edit:
I just checked the manual for both carb versions and it's a "Throttle Lever Stop Screw".

You've got me thinking now. I've got an older AME .049 with the non-removable round carb. I'll have to see how low it will idle. Unfortunately the closest thing I have to compare it to is a pre Revlite AME .061 with the square carb.

Carb Low Down for the Norvel
 

How cheap are yot getting the engines on eBay that it can offset the cost of a new cyl/piston set? In most of the auctions I see the seller wants near new prices.

screw
 

It is both a stop and an air bleed screw, that is the reason for the spring on the screw and the airbleed hole on the top!!!to check it I blew some WD40 through the air bleed hole and it came out the screw hole, I know what the parts book calls it but it was also converted for another language,I don't buy a piston and sleeve I buy a whole engine then do the the swap and resale or use them for c/l or to play with, when you have $1500 dollar helis you don't worry to much about $40 1/2a's or the price of 40% nitro, you just cut back on other things like feeding the family, or having cloths on your back being naked doesn't effect your flying, and sure the bald tires on my car don't stop well in the rain but heck there great on dry surfaces!!!

Carb Low Down for the Norvel
 

That is very interesting. I've always removed the screw, in fact Ed Stevens at Norvel recommended that I do that to allow the throttle to close. I've never been unhappy with the idle of my Norvels, even in a flying boat. Maybe I have been inadvertently setting the low speed to its leanest setting allowing for better transition.

Carb Low Down for the Norvel
 

I just took a look at 2 different carbs. I sprayed some WD40 into the air bleed hole of a round carb and nothing came out the screw hole. I tried it with the throttle open and closed and WD40 only came out the venturi. I've attached a pic of a square carb and I can't see where the screw hole could let air through. I wonder how many different carbs they made.