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Winter is here: choke time

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M

Member 10617

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There seem to be as many opinions on how to properly use a manual choke as there are car owners. Can someone bring order to this and come up with one procedure.

I have found, for example:

1. "Don't pump the gas with the choke out."

2. "I was always taught to pump it a few times, throw choke all in, crank over till it starts, open it part way, leave it to idle and warm up, then pull the choke off."

3. "Fully close the choke, start the engine. As soon as the engine fires, open the choke just slightly and let it run smoothly. Then, as the engine warms, slowly open the choke the correct amount to keep the fuel mixture right. When the engine is warm, the choke shoulld be full open."

4. "My experience is there is no hard fast rule as each car is different. Try pulling it out half way. Then try to start it. If it starts the first time, remember this for the next time. You should then reduce the choke back until the engine warms up and you drive the car normally without any choke."

5. "Pull the choke fully out (in the winter). Start the car. Do not press the accelerator. If the car does not start, then just slightly press the accelerator. Once the car is started, you will notice it is revving at high speed. I then slowly push the choke in a bit till the engine is running at lower revs but smoothly. Then I will drive off. Once the car is warmed up slightly, you can slowly press the choke full in."
 
Ed - there are as many "choke" techniques as there are cars, carbs, engines and weather conditions.

If you're not happy with the technique given on page 11 of the "Practical Hints" manual, then here's what I do if the engine's completely cold (not driven since the day before).

1. push gas pedal about halfway down
2. pull choke knob *fully* out
3. release gas pedal
4. ignition on
5. starter button

Usually fires within 3 to 5 seconds. Runs very rough on full choke. As it smooths out (about 30 seconds), push choke knob in halfway (first "catch"). Now the "choke" is off, but you're on fast idle.

As engine warms (watch the temp gauge), slowly push choke knob completely in to normal "warm" idle.

Of course, all this assumes your carbs (and ignition and timing, etc.) are correctly adjusted, and that your "choke" mechanicms are working correctly. Most aren't. The jet either doesn't drop on full choke, or doesn't return completely when choke knob is pushed back in.

Hope this helps.
Tom
 
Tom,

Yes. That helps a lot. I have been guilty of pumping the gas pedal, and I won't do that any more.

Many thanks.
 
You can pump a sidedraft carb ( US or ZS) all day and you will not add any gas to the engine, a downdraft carb, yes it has an internal pump. On a LBC I have always pulled the choke out on starting a cold engine. When it starts, I will adjust the choke as needed until engine runs smooth but at an accelerated rpm and car is moving. Every car has its own individual crank and run. Some will take full choke, some only part way.

Marv
 
:iagree:

Durn'd things each have their own personality. It can take some time to find the choke's "sweet spot" on 'em. It varies with severity of the "cold" on some, too.

Marv said:
You can pump a sidedraft carb ( US or ZS) all day and you will not add any gas to the engine
Click to expand...

mehheh. Can't count the number of cases where we've watched folks waggle the throttle blades three or four times on depression carb cars before even turnin' the key.
Some even continued the practice after having things explained to 'em. :shocked:
 
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