MOOORE CHOKE! Zenith side bowl
 

I have a late 31 with the side bowl carb. I was running a Tillotson on it until the Tillotson started giving me trouble. Kit and carb sitting on the bench... With the Tillotson, a cold start required pulling the choke rod, hitting the starter, then letting go of the choke rod. Car ran great from there.

After some running issues with the Tillotson, I re-installed the side bowl zenith and have been running that for a while. The problem is, when I start it first thing in the morning (cold for California), it does not want to run. I learned recently that if I hold the choke rod out and modulate it with the choke rod, I can make it “warm up” and run. It won’t run cold with the Zenith without modulated choking. I don’t think that is normal—any thoughts, ideas, experience to share here?

Re: MOOORE CHOKE! Zenith side bowl
 

Are you opening the gav valve until it warms up?

Re: MOOORE CHOKE! Zenith side bowl
 

I run a Model B Zenith carb (side bowl type) on my 1930 PU, using a Model A intake. A Huntington Beach cold start is just like yours "a cold start required pulling the choke rod, hitting the starter, then letting go of the choke rod". I pull the choke full out for about one engine revolution. Works great. I don't use the GAV, but this is common with the Model B Zenith. I hope this helps you.

Re: MOOORE CHOKE! Zenith side bowl
 

Could your Zenith float be set a bit too low?

Re: MOOORE CHOKE! Zenith side bowl
 

Help me understand a B carb with a side bowl ? Do you have a pic thanks Bob

Re: MOOORE CHOKE! Zenith side bowl
 

My error, the B carb inlet is at the front. Too many carbs on my mind

Re: MOOORE CHOKE! Zenith side bowl
 

31 Woody,

I agree wth TerryO about turning the GAV about one or one and a half turns until it warms up.

We have some winter mornings here in the I.E. as low as 26 degrees, but I don't start my car be cause it's too cold for us to drive around in an open Roadster. We wait until the temp outside warms up.

By the way, I bought our Roadster four years ago from Chuck Weaver in Lake Forest. He owned the car for 20 years. You may know him.

David Serrano

Re: MOOORE CHOKE! Zenith side bowl
 

try this trick when starting a cold engine:

Turn on the ignition, pull the hand throttle all the way down, keep your left hand on it. With you right hand pull the choke up. Step on the starter and let the engine crank over a few rev's. Drop the choke and the engine will light off. Immediately pull the accelerator hand lever back up to keep from over revving the engine.

What is happening is that with the butterfly full open and the choke closed the engine with a few rev's is sucking in a lot of raw gas and as soon as you drop the choke which will allow a burst of air to enter the engine will light off.

Tom Endy

Re: MOOORE CHOKE! Zenith side bowl
 

Tom is on the money here I think. I have a Zenith 3 sidebowl on my Late 31 coupe and I start it on cold Oklahoma mornings much as Tom as detailed. I don't have to give it that much throttle but I do advance it just past mid point and then from there just as he describes. I do start by turning the GAV just passed the half way point on colder mornings but quickly close it to a quarter open or closed.

Re: MOOORE CHOKE! Zenith side bowl
 

If you hang a late 31 sidebowl on a B carb with a banjo bolt you can hook a stock A gas line to it with just a little stretch of the line.I only know this because it is the setup found on my car that my uncle parked in 1954.I got the car around 1968,it took me years to find out that wasn't the original setup.It looks like it belongs there.

Re: MOOORE CHOKE! Zenith side bowl
 

You can also use two brass fittings from Fastnall on the B carb and use the original gas line on the Bob

Re: MOOORE CHOKE! Zenith side bowl
 

To reply to a few of the messages...
- The float is still a hair too low. I have adjusted it once but a really fast stop will stall the motor.
- I have not adjusted the GAV. A combination of lazy and ignorant.
- Using the hand throttle. That is what I was doing until I came up with modulating the choke rod for 30 seconds or so.
- I am not confident Tom’s suggestion of pulling the hand throttle down all the way and then making the necessary following adjustments would work. When it is cold, it acts like the carb does not have enough gas in it to keep the car running (low float, obstruction, or something). The car wants to stall. That said—Tom forgot more about Model A carbs just yesterday than I ever knew! Maybe I ought to listen.

Step 1 I need to do is finish adjusting the float level. Then I need to try the GAV adjustment method. Funny, but I never had any of this with the Tillotson. With that carb I just pulled the choke rod, hit the starter button and let go of the choke rod. Then I was on my way. Is this a Zenith only issue?