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birdbrain
12-23-2008, 10:11 PM
I replaced the choke housing in the summer. I am experiencing hard starting because the choke fast idle is not working. The flap is closed however what makes the fast idle engage? I don't know what I am doing wrong. anyone got a pic of what I need to look for?

KULTULZ
12-26-2008, 04:10 AM
Before we start, do you have a shop manual?

JohnG
12-26-2008, 03:13 PM
Questions:

* does the engine start?

* does it fast idle or not once started?

* does it run properly once warmed up?

* what carb is it? (Fomoco? Holley? other?)

john

Anders
12-26-2008, 04:09 PM
I hade a similar problem earlier this year. I appered as the guide to the choke link ( looks like a upside down piston with a rod ) got stucked as a pin that holds the "piston" and the "rod" got loose and therefor stucked, so nothing worked. It cost me two mufflers as the engine exploded several times before I figured that out...
But I guess itīs part of the fun owning a old car :o
Pic shows the rod and the hole where the pin should be.
I have a Edelbrock carb.

birdbrain
12-27-2008, 09:08 AM
I have the holley, yes it starts after alot of turning. It runs however not in fast idle mode, runs great once it warms up. It just started doing this, in the fall it was doing fine I have not removed the carb.

JohnG
12-27-2008, 09:52 AM
First you need to convince yourself it is in a good state of tune (timing & dwell good etc) so a weak spark is not the cause of poor starting.

Next, with the car stone cold, I would check the position of the throttle plate and see if it is excessively open. I have a vague recollection that a gap of 1/8" or less is desireable but I am hoping someone will comment on that.

On the Holley I have, on the passenger side there is an adjustment for the choke - a dial about 1.5" diameter. You could play with that provided you make a couple of marks to show you where you were before you changed it. I believe this dial allows you to change how much cold "choking" you get but again it would be good if others commented on this as I am no carb whiz. ( I personally have the oppoite problem at the moment - car starts instantly but runs too rich in between starting and being warmed up).

john

KULTULZ
12-27-2008, 08:47 PM
Are you the gentleman that was looking for a choke housing cover earlier? Did you find the correct one? If not indexed correctly (differing models) the choke will not operate correctly.

Here is an Ill. It is a FORD 4100 but of the same design.

http://www.hotrodders.com/gallery/data/500/4100_Choke_Mechanism.jpg

Do you see the fast idle adjustment screw? This will give you increased fast idle if everything else is operational and within specs.

An actual shop manual will make all of this much easier to understand.