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Old 08-22-2007, 12:19 PM   #7
77 350 Shorty Wide
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Join Date: Dec 2006
Location: Yakima, WA
Posts: 325
Re: Hard starting when cold

Hi and welcome to the board.

1.) Electric choke (simple explanation) has a small coil of wire inside a housing that expands and "uncoils" when electrical current is past through it.
This is connected mechanicaly to a butter fly valve in the air horn that will open up gradually as the spring warms up.

2.) Setting the choke is done by mechanical means. When you depress the accelarator pedal to the floor. The same spring will pull it shut because it has cooled and has coiled itself backup.
When starting cold, you should NOT stab the accelerator pedal, but rather depress it smoothly. This not only allows the choke to set itself it also primes the engine with raw fuel using one full stroke of the accelerator pump.

Ideally when the vehicle was "new" and not under extreme temperatures such as below 0, one full stroke would of been enough to start. Also when new the engine would usually start almost immediately after engaging the starter.
With many years and miles under it's belt and possible performance modifications later things tend to change. "As we all do when we get older, takes me a lot longer to get things done at 51 than it did when I was 25."

3. As stated earlier in another post, the "choke pulloff" is designed to give the choke a little breathing room once the engine starts making vacuum. The butterfly valve that was fully closed to aid in initial startup needs to be cracked open a little to let additional air in for the engine to keep running otherwise it will load up, flood itself and die.

4.) The entire choke system is really very simple and it will work great for many years once setup properly.

In your original post when you say "it takes a lot of cranks to get it started"
How long in seconds before firing are we talking about :01, :05, :10, :15? it's not unusual to see :03 to :05 seconds on a vehicle with some miles on it. I think you'll find most stock carburated v8's in good tune will need :01 to :02.

I know this doesn't answer all your questions, I was just trying to explain an electrical choke system.

Hope everything is going well and your making progress with your problem(s)

God Bless, Terry
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