Ron Pilger
Senior Member
Hello experts. I have just rebuilt my stock 32 4 cyclinder carb. The end result is a mixture significantly too rich. What should I try? Thanks.
model B 4 cyclinder carb adjustment
- Thread starter Ron Pilger
- Start date
Did you rebuild the carb with the new jets available from most suppliers? These typically flow waaay too much fuel. Best to use cleaned up originals.
Also, can you notice the changes resulting from small adjustments of the GAV? If not, then the valve seat drilling in the lower casting may be worn wider than the maximum 0.125 inches. In this event, your carb will always run more or less on the rich side because it allows too much fuel into the main jet - cap jet network. Unlike the Model-A carb, the B-carb was designed for the GAV to be completely closed after warm-up.
Also, can you notice the changes resulting from small adjustments of the GAV? If not, then the valve seat drilling in the lower casting may be worn wider than the maximum 0.125 inches. In this event, your carb will always run more or less on the rich side because it allows too much fuel into the main jet - cap jet network. Unlike the Model-A carb, the B-carb was designed for the GAV to be completely closed after warm-up.