72 dart 318 starting sequence

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Chub380

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How would you guys say to start this car from a cold start? Everything is stock la318 2bbl carter. Like with my 77 k10 quad jet I put the pedal to the floor hold for a second release and starts right up even at cold temps. Just curious if this would be close to the same for my daughters dart?
 
On my stock 72 318 2 barrel dead cold I push the pedal down around halfway once. Enough to set the choke and get a good squirt from the accelerator pump. That’s it. Twist the key and it lights right off. Blip the throttle a minute or so later and she’s off the choke and running.
 
You shouldn't need to hold it for a second, but one pump of the gas pedal upon cold start will inject some gas into the engine through the carbs accelerator pump and will set the choke. This is standard cold start procedure for all carbureted engines.
 
How would you guys say to start this car from a cold start? Everything is stock la318 2bbl carter. Like with my 77 k10 quad jet I put the pedal to the floor hold for a second release and starts right up even at cold temps. Just curious if this would be close to the same for my daughters dart?
Yes for cold starts. Warm or hot starts I don't ad gas by hitting the gas pedal, i just crank the engine.
 
Ok that’s what I was trying with little luck, then the engine seems to be flooded so I held pedal to floor thinking this would open the air flapper/choke but it doesn’t so if I wire the flapper open it fires right up. Any ideas?
 
When the engine us warm or hot the choke should be open. If it is closed you have some issues that need repaired or adjusted.
 
Yes that is correct it does open on its own when it warms up. That’s not the problem it’s only when I’m first starting it. Maybe this is a better way to phrase it ,if the car is flooded isn’t the right thing to do is press the pedal to the floor? I guess I was assuming when you pressed the pedal to the floor that should open the air/choke flapper,it does not ,it stays completely closed. if I go out and wire it open it fires up and idles just fine. Sorry that I’m not super familiar with this stuff.
 
Let's go back in time. To when these girls were new. And how you are SUPPOSED to start them

You floorboard the throttle and let it up. ONCE unless it is extremely cold, say, below zero, and even then "depends on the car."

This is a "learned" procedure. Often on these old girls, in "warmer cold" weather, say, around freezing or maybe 40's F you didn't need to floorboard the throttle, but learn to just partially move the thing enough to actuate the choke. This did not pump a particularly large shot of fuel into the carb

Then you crank it. WITH FOOT OFF THE THROTTLE At that point the choke should be set fully closed. When the engine fires, or even tries, the airflow will somewhat pull the choke open against the spring, allowing some air. As the engine fires and speeds up, and generates engine vacuum, the choke pull off pulls the choke open a certain amount which is set by an alignment procedure and gauge (drill size)

Then as the engine starts to warm up, and the choke state relaxes, "kicking" the throttle lightly will release the high idle and bring the thing down to an intermediate idle speed or even "warm curb idle."

BEAR IN MIND that a properly adjusted choke DOES NOT EVEN NEED an accelerator pump shot!!! The extra fuel to start can be provided by the choke itself "Pumping the gas" multiple times should NOT be necessary, except in extreme cold, down into the "20's F or near zero
 
By the way, find an owner's manual. Some of the older cars had the cold start procedure on a sticker on the sun visor
 
Owners manual is good idea.
Its funny that in '72 Chrysler was telling its techs that some starting issues can be due to the owner's expectations or techniques.
1972 Imperial & Chrysler Engine Performance Facts & Fixes Service Book (Session 291)
But in '73 it made that the subject of an entire tech session. (the '73 emissions stuff made this more important)
1973 Imperial and Chrysler How To Get Them Started Repair from the Master Technician Service Conference Series (Session 307)
The 1973 Chrysler Cars & How To Get Them Started Movie from the Master Technician Service Conference Series (Session 307)
 
2 thing not addressed is the choke pull off and the choke un-loader.
Choke pull off is vacuum operated and if set right will open the choke slightly after the engine starts and vacuum increases.
Choke un-loader is manually operated and opens the choke when the accelerator pedal is pushed completely to the floor in a flooded condition
Both need to be adjusted correctly.
 
For a HOT restart it helps to crank with the accelerator about halfway. AFB/Edelbrock carbs benefit from this technique especially with easy-to-boil ethanol blended gas.
 
Thanks a lot guys, never even thought of that there’s a pristine Manual in the glove box, I hate even opening it though because of how nice it is, I’m just funny that way. The car had all sorts of cool stuff like that like the original dealer paperwork in great falls montana old tires sale sheets ect. Another thing I learned by reading this is I think I need to put the stock air cleaner back on and hook up that little vacccum line before going any further I just plugged it. So when people always say if you think it’s flooded push the pedal to the floor and hold it ,what’s happening in the carb both with fuel and air? Thanks so much for the good reading so far. She only drinks premium with no corn juice, lol. What cool reading Mattax!
 
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So when people always say if you think it’s flooded push the pedal to the floor and hold it ,what’s happening in the carb both with fuel and air?
What happens is both the throttle and the choke are held open. This results in air but no additional fuel flowing into the intake.

At idle and off-idle fuel flows from the bowl to the intake because of the difference in pressure.
Another way to think about it is the pistons moving down create a vacuum under the throttle plate.
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When the choke plate (not shown) is nearly closed, that increases the pressure difference and reduced the air mass density.

The action of opening the throttle does actuate the mechanical pump shot. So that's why pumping the throttle is sometimes useful when the intake is completely dry. But with a flooded carb is counter productive.

Opening the throttle and choke fully and holding during starting results in nearly the same pressure at the idle port as in the fuel bowl (atmospheric) .
Air comes in and mixes with the excess fuel sitting in the intake and cylinders.

There's some MTSC sessions on how carbs work here
Master Technician Service Conference - Chrysler's Training for Mechanics
Look at Carb Fundementals in either 1966 or 1970
 
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Thanks so much what an explanation! so if the choke doesn’t open with the pedal pushed down what might be wrong I’ll post a pic in a couple minutes when I leave for work. Thanks again
 
Thanks so much what an explanation! so if the choke doesn’t open with the pedal pushed down what might be wrong I’ll post a pic in a couple minutes when I leave for work. Thanks again
When the engine is cold-
Opening the throttle should cause the choke to close.
Opening the throttle to wide open should physically cause something on the throttle shaft to physically push the 'unloader' tang, which rotates the choke open.
Every carb design is a little different so need to see what's there.
 
Thanks so much what an explanation! so if the choke doesn’t open with the pedal pushed down what might be wrong I’ll post a pic in a couple minutes when I leave for work. Thanks again
Probably just an adjustment. The choke unloader is different in all carbs. If you look at the choke linkage at full throttle you will see a tang that engages the chole linkage and cracks open the butterfly. You may catch a diagram if you Google it.
 
C08E7912-65BB-4EF6-BC63-3CC4457E8955.jpeg
It’s hard to see the black arrow but I think that’s what you meant
 
It just cracks it at full throttle, not nearly fully open maybe that’s how it should be?
 
Thanks guys I have a lot of great reading material for all night long, I’m thinking 9/64” is probably almost what it was I guess I was thinking for a flooded situation it would open all the way. Thanks all you guys!
 
That looks like it.
It just cracks it at full throttle, not nearly fully open maybe that’s how it should be?
I agree with Mike, I think that's about right. It needs to be open enough so its not restricting.
The factory service manual will have the specifics.
For example this is from the '71 Plymouth FSM
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The amount of knowledge/ info on here is amazing. I am truly thankful to you guys. I got 12 hours ahead of me to read all this material.
 
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