1930 Model A pickup refuses to idle correctly

[Wooly1]

I just bought this 1930 Ford Model A pickup and it's had some issue. The latest after fixing the no start issue, swapped battery polarity and dirty connections, is it will not idle. I rebuilt the carberator, was dry and crusty, cleaned it, new jets and brushed the passages as much as possible. It will start and idle on the rebuilt tillotson carb but only at a high rpm "12-1500 rpm ish" and requires a lot of choke to get started. After it starts the idle is very high, and if I adjust the idle throttle screw down it dies. If I rev it and let off quickly, it dies. I have set the mix screws as recommended and adjusted them to no avail. I checked for vacuum leaks and found none. It will respond to starter fluid while running at idle so I don't think its running to rich. The exhaust doesn't smell rich either and did not appear lean such as hot exhaust pipe. I swapped the tillotson with a zenith of another running model A and it refused to start no matter how much I tried. Checked fuel flow to the carberator and very good flow. At this point the only thing I haven't touch is the timing. I checked the distributor, all points look clean, condenser is relatively new from what I can tell.

 

Could timing cause this problem?

Edited January 23, 2023 by Wooly1 (see edit history)

[carbking]

See this was your first post, WELCOME!

 

Testing is necessary

 

In order:

 

(1) Compression

(2) Ignition (includes timing, and especially the condenser)

(3) Then look at the carburetor

 

Jon

[Gary W]

Be sure your GAV inside the car is not too wide open, or shut down.  My "A"'s run with the GAV 1/4 turn open.

I still follow the book when I start the cars.

I open the dash adjuster one full turn (GAV)

Step on the starter

Pull choke momentarily

She starts right up at this point

Advance the spark

Retard the throttle to a faster than normal idle

Close down the GAV (dash adjuster) to 1/4 open

After a couple minutes of warming up, retard the throttle down and she's ready to go.

 

If you have vacuum wipers, be sure you are not pulling in air through a worn vacuum hose

Check your idle adjusting screw on the carburetor.  There will be a sweet spot between too closed off and too far open.

Check the point gap

Check your spark plug gaps

Check your coil