Manual chokes: why not?


#1

When I was a youngster, I learnt how to drive a car with a manual choke. It didn’t seem like a big deal. Although I never had a reason to use it other than cold starting, it seemed like it could be used otherwise occasionally. Balkamp makes a cable one can use to convert to manual choke. I considered buying it back when my choke ‘broke’ 12 years ago. Did we switch to automatic chokes for any reason other than careless people forgot to use their manuals?


#2

I would say it’s because of emissions, plain and simple


#3

I am not sure it had anything to do with emissions. My Dad had a 1940 Chrysler for a year and it had an automatic choke. We didn’t have an EPA back then. It seems to me that the more expensive makes had the automatic chokes while the low.priced cars had a hand choke. I know the Chrysler, DeSoto and Dodge in the 1940s had automatic chokes, but the Plymouth had a hand choke until 1949. I know that after 1946 the Chevrolet was the only car in the GM line that had a hand choke. Interestingly, my 1948 Dodge had an automatic choke, but it had a throttle control to increase the idle speed. I know as late as 1964, the full size Ford 6 had a hand choke. My 1961 Corvair had a hand choke that closed the choke butterfly on both its carburetors. That was the only year Corvair had a hand choke. I once had a cheap MTD lawnmower and the Briggs and Stratton engine had an automatic choke. (No, it didn’t have a primer bulb).


#4

Manual chokes were cables that could rust or just become hard to use.- It was easy to flood engines even by people who knew how to use them-they didn’t have automatic shut off-with computer driven fuel injection why would you even want one.

I am sure there many more reasons for this silly question.


#5

Why emissions? Because people push it in too late, or forget to push it in, and run too rich?

There was some reason to use it other than cold starting, but I forget what it was. Anyone remember? Mr triedaq seems knowledgeable.


#6

One use for the hand choke was to cool the engine if it started to overheat. You could pull out the choke and let up on the accelerator. The raw gasoline hitting the piston tops would act as a refrigerant. It was particularly useful in mountain driving. When you reached the peak with the engine temperature so high that the coolant was ready to boil, you could pull the choke as you descended from the peak and cool the engine in short order.


#7

To make black smoke?

I don’t believe it was possible for manufactures to pass the EPA emissions certification tests and long term performance tests in the 1970’s with a manually operated choke.

It has also been decades since manual chokes were used on lawn mowers, small engines must meet emissions standards. Last year my neighbor bought a new mower, it has no throttle control. The engine races at high speed at all times for clean operation, too noisy for my approval.


#8

That is a good reason to take the choke operation control away from the driver, that causes a lot of pollution. The rest of us have to breathe that air.


#9

Sorry but I just can’t see it had anything to do with emissions. My lawn mower has a manual choke and my new snow blower has a manual choke. Nothing to do with emissions. My 59 VW had a manual choke but our 57 Ford was automatic. My 59 Pontiac was automatic. I think it had more to do with the goal of just turning the key and the car would start. The more expensive the car, the less you had to fiddle with to start or drive it.


#10

Perhaps it is my proximity to California, lawn mowers, ATVs outboard motors etc. are regulated in the southwest.


#11

Manual chokes: WHY??

Let’s bring back manual timing and mixtures while we’re at it.


#12

Manual chokes started giving way to manuals long before emissions were even thought about. By the mid 50s most cars had automatic chokes. The hand chokes were simpler and more reliable especially here in the rust belt. the cables of the manual were easy to keep lubed, the automatics, not so much.

Most women did not like the hand choke. In the 40s and 50s the girls weren’t supposed to be interested in the mechanics of cars but the guys were.

Today young people of either sex don’t seem to be interested in the mechanics of cars.

I think that is why we get so many questions about “What is wrong with my car and is it expensive” that don’t give us any information about the car or what it is doing. I think if I see one more “What is wrong with my breaks?” I am going to scream.


#13

I had a car with a manual choke and for the most part I was using it as my “turbo” when I needed to go faster. Nowadays, I think the slowest car on the road is faster than what I was driving.


#14

I would suspect the main reason for automatic chokes would be to remove another aggravation step requiring input from the driver.

Why manually roll your windows up and down if the motor will do it for you.


#15

Someday people will be asking the very same questions about cars you must drive MANUALLY!! OMG! You mean you had to actually control the car yourself? With your hands AND feet??? HOW is that possible?

They already ask this question about manual transmissions, crank windows and the like.


#16

I read a story years ago concerning a British woman who had purchased a new car. She complained to the dealer that it was running poorly and belching black smoke. It was checked and nothing malfunctioning was found. They ask her to drive the car with a ride along mechanic. She got into the driver seat, pulled the manual choke all the way out, and hung her purse on it. Of course when she had arrived at the dealership she retrieved her purse and pushed in the convenient ‘purse holder’. I have had several vehicles with factory manual chokes and have installed a couple of manual conversion kits. Now I let the ECU adjust fuel/air mixture as needed.


#17

I have two motorcycles, one with EFI and one with four carbs and a manual choke. I dislike wasting fuel and leaving the smell of unburned gasoline behind when I use the choke. I’d much rather startup and go.


#18

That tale originated with The Model Garage, which was a monthly serialized fictional account of car repair problems, and which appeared in either Popular Mechanics or Popular Science, back in the '50s & '60s.
I subscribed to both mags, so I don’t recall which was which at this point. Or, perhaps that monthly article appeared in Mechanix Illustrated, which I also read from time to time. The old memory is not perfect at this point. :sweat:

Anyway, the protagonist of those monthly tales was Gus, the crusty old mechanic who could diagnose things that mystified every other mechanic. After Gus took a ride with the woman, he observed that her handy purse hanger was actually the manual choke control, and after instructing the woman about the simple remedy for her poorly-running engine, he refused to accept any payment for his services. I think that Gus was later Canonized…


#19

As ‘coalers’ do today?

And manual cranking!

This story was updated with a driver using the CD player as a cup holder.

I would think a purse hanging on the choke would swing around, hit the driver in the knee.


#20

Does fuel injection even use chokes? I reckoned it simply richens the mixture by injecting more fuel. Although, some EFI motorcycle models, the Suzuki 1250 Bandit in particular and possibly others did have a secondary throttle that was servo controlled, maybe you could call it a choke, but it didn’t just get used for starting a cold engine. It was more to keep the rider from giving the engine too much throttle at low rpms, sort of like vacuum operated secondaries in four barrel carbs.

Choke butterflies didn’t just richen the fuel mixture, also the vacuum behind the butterfly lowered the boiling point of gasoline so it would evaporate more readily. That’s why not completely warm engines would idle and run OK at low throttle openings but fall on their face if you completely opened the throttle. With the high manifold pressure of a completely open throttle, the gas wouldn’t evaporate enough to give a ignitable mixture.
I suspect that with “throttle by wire” EFI systems, the CPU is programmed to limit throttle opening while the engine is cold to keep the manifold vacuum high enough to boil the gas into vapor.