Small Engines (Lawn Mowers, etc.): B&S Carb Bowl not filling with gas, overhaul kit, gas filter

Question
These forums have been awesome. Today I fixed my Homelite
weed eater because of information I found. I've also gotten
close to fixing my Troy-Bilt mower with a B&S 127600, 7 HP
OHV. The mower just died the other day, but had been
cutting out and dying with increasing regularity. The
difference this time was I let it run out of gas. So I'm
sure some gunk at the bottom of the gas tank surged into
the carb. I plan to add an inline gas filter when it is
fixed.

Okay, so took off the car and soaked it, blew out openings
with compressed air, added new air filter and spark plug,
emptied all the gas out and put in new (the gas that was in
there was not old but wanted to start fresh). I noticed
that the float seemed to hang pretty low when I reassembled
the carb, and I was worried it would not open, i.e., that
it would hit the bowl cover before going low enough to open
the valve.

When I put it back together it would not start. I checked
for spark, no problem. So I took it back apart and pulled
the bowl cover low enough that the float released the gas.
I let the bowl fill, put it all back together, primed, and
boom, started and ran for a good 1 1/2 - 2 minutes, then
died.

Through many cycles of this, I am sure the issue is the
bowl not filling, so when I do it manually the mower runs
until it uses up that gas.

My question is, by soaking the carb in cleaner, could I
have screw up the needle valve seat? The float is plastic,
so there is nothing I could have bent to make it need to go
lower to open, and I can't figure out any other reason for
this change.

If I did screw up the carb, would you recommend an overhaul
kit or just replacing it, at about $40? I was so fired up
to get it running...I grew up working on B&S engines before
moving on to car engines, but that was a long time ago. I
almost got there.

Thanks for taking the time to answer questions...I
appreciate it.

Answer
What did you soak the carburetor in?

Send me the engine type number as well so I can look up your carb.

I am assuming you have a float bowl.  If you remove the float bowl nut does fuel flow out the bottom of the carb?  Most float carb do have an inlet needle seat, viton/rubber.  With the type number I can look it up.

Eric