Hi James,
It really takes a dumb person to write this much to answer a dumb question, but, based on your initial, very intelligent questions:
"I am having trouble with the carb. It is over loading, sputtering, and backfiring through the carb. I've had it apart and cleaned it but it is still getting too much gas. It will run out while the engine is running. I have read in some other threads about checking the float valve but how do I do that? also could this flooding be the cause of the sputtering and backfire?"
And like all of the other kind gentlemen willing to assist, with all of us not being able to "see" & "hear" what you are experiencing, or if your gas tank is cruddy, here are a few very old vintage suggestions:
Part 1, Causes:
1. First, if you still have your other Model A, you could try switching out entire components such as the carburetor, distributor, etc., to diagnose causes of the engine not functioning properly because of a component problem; but I'll assume you do not still have you other Model A; so,
2. Second, if the carburetor is flooding & getting too much gas, the only 3 carburetor parts that I can initially think of that can cause carburetor flooding are:
a. Choke: Your choke is closed & not open all of the way; hence, sucking more fuel & far less or no air; and/or,
b. Float: Your float is either leaking & sinking in lieu of floating; not adjusted properly; and/or, is hitting the sides of the carburetor bowl; hence, not moving up & down to operate the float valve which stops the fuel flow when the float actually "floats". This is also known as the float is "sticking" or "getting stuck" .
c. Float Valve: The shut-off element in your float valve is not sealing the float valve after the carburetor bowl is partially full of fuel & the float is "floating"; and/or the float valve has no sealing fiber washers and/or no impermeable "red" washer(s) which are designed to seal fuel flow. A dirty tank with dirty fuel can allow dirt to lodge in the float valve & keep the float valve in the "open" position causing bowl flooding.
Part 2, The Fix:
A. If not already on hand, please first go to a parts store to buy a pressured spray can of "any" kind of "carburetor" cleaner formulated to clean carburetors.
B. Carefully take your carburetor apart into 2 halves & remove the float. Then proceed to a stove, fill a small pot with water, allow the water to boil, turn off fire so you see no boiling water bubbles & turbulence, & submerge the float in the hot water.
C. If you do not see small bubbles exiting the float you do not have a float leak; however, if bubbles, mark bubble exit hole(s) with a lead pencil where the float hole(s) have to be sealed with solder. If soldered, try again to repeat the leak test. If float is bent up badly & leaks, just order a new float with float pin.
D. With a wrench, remove float valve which contacted the float near the float hinge. With spray carburetor cleaner use the combined compressed air & fluid to clean the float valve & the float valve opening in the top half of the carburetor. If it has a rubber (Viton) tip, it could have partially dissolved with new 10% ethanol gas or have gotten disfigured if over compressed when setting float height -- if so, order a spare float valve with a "metal" tip -- never a bad idea to have a spare float valve. Did the float valve have a "red" washer? If not call to order a at least 2 sets of float valve washers. Next, dry fuel out of float valve & blow in it with the shut-off device open & closed -- with device closed, there should be no air passage. Reinstall float valve initially with one (1) "red" washer(s). It can be fine tuned much later.
E. Reinstall the float with float pin. Make sure the float cannot move from side to side on the hinge pin by slightly compressing the steel hinge pin retainers with a pliers -- if the float can move side to side it can get stuck & hang up on the sides of the bowl & cannot rise & float upwards to close the float valve.
F. Initially, turn the top carburetor half upside down & insure that the soldered seam in the float sits "level" when looking from the "front" side -- if not, carefully bend the float arm connection at the float until the float seam is perfectly level & "parallel" to the joint between the carburetor halves.
G. Next turn the upside down carburetor top half 90 degrees to look at the float from both sides. A rough initial setting that will get a Model A started every time is to provide the soldered float seam "parallel" to the joint between the 2 halves. Bend float arm at float & adjust. Millions of carburetor floats on all 1920's & 1930's vintage cars were set "parallel" & "level" this way by vintage mechanics.
H. Remove one jet at a time & spray cleaner through each brass jet hole until fluid exits indicating it is clean -- do same with all threaded holes in the cast iron carburetor.
I. Turn carburetor top half upside down & back again to insure the float both "closes" & "shuts-off" the float valve & allows the float valve to again "open" -- listen for the "click".
J. Reassemble carburetor -- then listen for float valve "click" prior to installing same -- if "no" click is heard, disassemble & adjust float because the float is "sticking" ..... unless you are partially deaf like me where I ask my wife to listen.
K. Install carburetor & let us know what happened with carburetor flooding.
L. Float level fine tuning can be accomplished later using Renner's fuel level tool for measuring & adjusting exact fuel levels.
