Weber Issues

S

sandbug

Member
While I wait for Sam at Arizona Ford to answer the phone, I thought I would ask here. Sam is very helpful, but he's a busy guy.
We are having some issues on the Weber 32/36 (we got it ten years ago or more from Sam).

It seems to idle fine, but when you stomp the gas pedal, it goes into stall. It's sucking air at this point, and can and will backfire.
We replaced the power valve. Have a carter fuel pump on it from Sam along with his lines.

In the bowl, you can see gas percolating through regardless of the engine running. A push of the power valve shows one side spraying. Is the other bowl supposed to get a spray too?
So many theories on it's timing (we set the timing).

Here is a video of what is happening.

https://youtube.com/shorts/JxhKehHganw?si=pc8Ru4VqLmfFUE6B

Thanks for the help!
 
You need to re jet the carburetor. I put a much larger jet in the second (36 mm) throat on my Weber. The acceleration pump only works on the 36 mm throat. I used a smaller jet on the 32 mm throat because I use that most of the time and it helps with fuel economy. The throats are progressive. The 32 mm throat opens all the way before the 36 mm throat starts to open.

https://www.piercemanifolds.com/ sells a tuning guide booklet. They also sell rebuild parts and different size jets. They are in Hollister, so it is a 5 hour drive up Highway 5.

You only need the smaller float valve seat. The Model A will not use enough gasoline to need the larger one and the larger one tends to leak.

You can also experiment with the idle jet for the 32 mm throat.

It will take some experimenting to get the carburetor working well. Also, do not trust the jet sizes but measure them using precision pins or small drill bits that you measure with a micrometer. Use the end of the bits that do not do the drilling. You can also drill out the jets, a little at a time, if you need a larger size.

Each engine is different and each carburetor is different. So what worked on my carburetor/engine may not work on yours.
 
Last edited:
While you’re waiting for Weber parts , check the fuel supply pressure at the carburetor, also check the fuel inlet filter in the carburetor. One last thing too check is ohm the coil primary terminals ! I was having acceleration issues and chased my tail checking the fuel system, my 6 volt coil ohm’d 2.2 way too high, replaced the coil fixed my issues
 
You must log in or register to reply here.
Back
Top