Stalling on stop update

JtownJoe

JtownJoe

Senior Member
Thanx for all the replies, found a few issues that when combined probably account for the stalling. (1) there is some wobble in the throttle shaft that does leak some air when I wrapped it it teflon tape it helped. (2) There is no baffle in the float bowl, might have some bearing on it. (3)The idle mixture screw made it a little better when it was set at about 7/8 of a turn out. It will now keep running if it I can come to a very gradual stop.
It will always stay running if I am stopping on an up hill grade or apply the brakes in reverse but will always stall on a down hill stop. As much as I like the B unit I will have to run the New Zenith for now, It may not have quite the power the B has but it is so dependable & I can also use an air filter with it.
 
Sounds now like a little tweaking on the float height done now just like you would do on a Model A Carb may now help to solve your sudden kill situation. Make sure the flat area of the float is not worn where the float valve rubs against it. If it is you can solder it up and file it flat again. You can bend the float to be a lower level so the surge of gas in the carb at a suddne stop will not float the float all the way up to close the valve. Make sure the small rod that holds the float hinge is perfectly flat by rolling it on a flat surface. It is has a kink and not flat it could cause you issues like you have been experiencing.
 
Another issue I have found on rebuilding carbs is the Gasket that you buy today for the two halves is larger on the bowl side and the float hits it, keeping it from not floating. If you have an older gasket compare to the new repo and you will see.
 
Thanks for the update.

If you do get the B carb sorted out some day, here's a picture of one that's been balanced for use with air filter. Note that this is the backside, so it's not quite as ugly as you might think--maybe no worse than the new Zenith, which I too am using. The mod probably could be done with more discreet, metal tubing.

ModelBcarbs010.jpg


Steve
 
You need to check the flow rate of the compensating jet and the idle jet. This allows fuel into the center area that helps the car during idle. Also check the height of the main jet and to see if you have enough gaskets on the top and bottom half to have approx 5/16 float height from the top of the bowl.
 
Joe
A compensator jet that is too small can cause stalling when stopping especially at the bottom of a hill. Check the jet size and compare to Ford specs. If your car is backfiring as you decend a grade this is a clue that it is running lean due to the secondary well being starved for fuel. The effective fuel level is lower when the car is headed down hill and this reduces the head pressure on the jet resulting in reduced flow to the secondary well. This approach worked for me.

Roland
 
Roland/Pittsburgh said:
Joe
A compensator jet that is too small can cause stalling when stopping especially at the bottom of a hill. Check the jet size and compare to Ford specs. If your car is backfiring as you decend a grade this is a clue that it is running lean due to the secondary well being starved for fuel. The effective fuel level is lower when the car is headed down hill and this reduces the head pressure on the jet resulting in reduced flow to the secondary well. This approach worked for me.

Roland
Click to expand...

Yes Roland what I was saying. Most folks don't realize te function of the secondary well and the compensator jet. Flow rate is very important.
 
You must log in or register to reply here.
Back
Top