Holes plugged in main body.

[PUO]

Carb#17057213 just pulled this reman carb apart and found plugs in two holes in the main body. Of course they fell out. Looking at the gaskets it seems to be an air bleed.


I also pulled a parts carb apart (Holley reman) same # 17057213 and found the holes plugged


What is their function? Do I plug these or leave them open?  I just went thru the carb on my 78 chev truck #17058213 and now there is a slight off idle hesitation could that be due to these air bleeds?
The engine in my truck is stock 350 and the carb I'm rebuilding is going on a stock 302 ford

Any help would be appreciated

[Frank400]

Does not look like an air bleed to me, idle air bypass maybe ?

[17058263]

tthats is a 1972 carb not a 77 like the number sayes must be a restamp.  and the holes are for idle bypass air. it must have the holes in the throttle plate. for them to work,

[Cliff Ruggles]

The lead plugs are part of the commercial "remanufactured" process.  Those companies were building "one size fits all" units, so they blocked off the idle bypass air passsages in the main casting.

That carb is a special unit, using the later single main airbleed design on the early divorced choke casting.

They had a very unique calibration from the factory, but it's been "butchered" up during the remanufacturing process.

Most likely they also clipped the post off the bottom of the power piston for the APT adjustment, and put in "generic" jets and metering rods as well.

I can supply the correct parts to get it back in calibration for any particular application, etc.....Cliff