Electric choke question

I have an '81 Chevy with a 4 barrel carb, and an electric choke. I had the carb rebuilt last summer, and it has been working great up until about a
month ago. Cold starts, as in, first start of the day, I always used to press the pedel to the floor and release it, then turn the key. It would start up right away and go to fast idle. Now that's not working. I think it's the choke, but am not sure. Now it does start right up, but dies right away. Then I have to pump the gas pedel 4 or 5 times to get it to start.
The truck was sitting for 4 months without being started, if that helps, but I don't think that makes a difference.
My understanding was that pressing the gas pedel to the floor sets the choke to an almost closed state, and that in turn feeds the engine more gas than air, and allows it start better when cold(first start, not necessarily cold weather), and as the truck warms up the choke opens up.
Am I on the right track?
Any help is appreciated. TIA.
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There is a choke pull back diaphram, that is supposed to open up the choke for a set amount,after starting, so that the engine can get enought of air, to keep running. Mounted on the carb. I don't know if you have one or not... My 2 cents worth!

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On Fri, 01 Sep 2006 22:43:07 GMT, "Andy & Carol"

Yes there is a vacum dashpot on that carb but it is likely not the problem. It likely is the choke spring itself. As they age they loss tension and lean out which is confirmed by the need to pump it 4 or 5 times now. Two solutions here, the first is to replace the choke coil. The second it to readjust it. I use the later. They usually have a pop rivet or two locking them in place for emissions adjustments when new but you can drill them out and install small screws it there place and adjust it to proper function again. ----------------- TheSnoMan.com
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SnoMan wrote:

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SnoMan wrote:

I worked at Rochester Products for Many years and we built all of the original equipment quads. Snowman is correct about the spring tensions but there were also many many adjustments that involved bending the linkages and cam adjustments on the choke side of the carb as well as the dashpot adjustments. If your reasonably sure that there was no accidental bending of the cams or links the best way to go is to make the adjusments as suggested by snowman and also take a can of carb cleaner and making sure all of the cams on the choke side are clean and working freely as many times they get gummed up amd stop functioning properly.. hope it helps.
Noelbiker
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On 2 Sep 2006 10:03:07 -0700, " snipped-for-privacy@gmail.com"

These are all good points but typically it is the spring that gets tired. I have a 27 year old vehicel with one that I have had to readjust 3 or 4 times in the last 21 years. ----------------- TheSnoMan.com
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Mine has 3 Screws that looks like would allow me to remove the coil. The screws are located at apporx. 9 O'Clock, 3 O'Clock, and 6.
But before I do this, maybe I will try the carb cleaner. But I don't know where the cams are. Can I just give the whole thing a good spray, getting all the linkages and such, and what about inside the carb?
Thanx.
wrote:

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wrote:

You need to readjust it or replace coil because they do age and even if you replace it it will have to be adjusted correctly as well that is why I would try adjusting it first. A cleaner will not hurt but it will not fix you problem. Ageing of those coils is very coomon on old vehicles. They always go lean when they age and if they go rich, you have other problems generally. ----------------- TheSnoMan.com
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My neighbor, who did his 3rd year mechanics, but never went back, adjusted the choke so that it was leaned out to almost the max. It now starts perfect. He says I'll probably have to richen it when the weather turns colder, but it does start and run perfect now. My question is: does the engine running that lean, hurt the motor in any way? The choke was set at dead center between lean and rich.
I know if it runs too rich, it will hesitate off the line, but what would it do if it was running too lean?
Like I said, it's starting and running perfect.
TIA.

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wrote:

As far as warmup cycle, the only problem you will have if it is too lean is hesitation and stalling. If way too rich the extra fule during warmup can increase engine wear during warmup because of it deluting oil on cylinder walls (we are talking smoking black rich here). Not to metion lower MPG too. ----------------- TheSnoMan.com
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If the engine starts, the spring seems as though it has enough tension.. The pull back has to be adjusted..very sensetive adj, the engine is shutting down because of lack of air...

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