Carter AVS 4429s Choke...School me!

[Macdon221]

Good Day All,

Carter 4429S....On a 68 440 with stock intake manifold.

The carb was restored by one of the recommended carb rebuilders on this site. The carb works fantastic and looks great. Idles great and runs perfect though all ranges of power. No issue. I went through the service manual and have checked and measured all the tolerances and settings. They are all bang on.

To the choke...Car heats up, the divorced/well-choke pulls and fully opens the choke when hot. Closed fully when cold. The choke diaphragm operates fully with vacuum and does not leak. It will hold in place no issue with vacuum. The diaphragm link is adjusted as per the manual, and is set so that as soon as vacuum is applied it starts to "help" the choke to open upon start up. Fast idle speed is set perfect on the 2nd highest step

The problem...immediately after start the choke is still closed a little too much...and the engine is running too rich. If I open the choke just a little more by hand...instant smoothness. The engine warms...the choke slowly warms and then it full comes off/opens no issue. Off to the races from there.

Now knowing that it is all set up to factory specs...how do I get that choke to open a little more right after start?

Is the diaphragm link where I should be providing fine tuning to, to open the choke more after start with vacuum? ie. close the bend a little more.

Or should I be adjusting the fast idle connector rod (shorter) on the throttle side to open the choke a little more at the start?

Something else?

Cheers

 

[pnora]

Adjust the link on the choke pull off so it opens the choke a bit more.

 

[Orig69]

Do you have the original insulator installed in between the carb and the intake manifold?

 

[Macdon221]

Thick gasket.

 

[Orig69]

Yes, a good quality rebuild kit usually comes with one.

 

[pnora]

Do you have the original insulator installed in between the carb and the intake manifold?

What would that have to do with fixing his problem?

 

[R413]

Yes bend the linkage on the choke pull off at the U bend. A little bit will do it, and this is not uncommon as different engines want different things.

1968 does not use a thick gasket. Thin only. If you do then the choke will be AFU.

The thick gasket started in 1970.

 

[jimbosride]

If it has this link it designed to be bent to adjust choke pull off .....

No expert here

 

[Macdon221]

OK...that's what I have done to start is pinch the bend just a little more. Let it cool overnight here and then try it again tomorrow.

Thanks for the replies so far.

 

[pnora]

OK...that's what I have done to start is pinch the bend just a little more. Let it cool overnight here and then try it again tomorrow.

Thanks for the replies so far.

You seem to have a grasp on what its doing and what to correct it. Pinching the link a little closer on the loop/bend is the right way to go. I would rather be a touch lean than to rich. Factory settings get it close. Due to age and wear on the holes and links a guy has to dial it in to where it will work right.

 

[Macdon221]

Ok. I am a pretty detailed guy...and it was set up perfectly as to the settings in the FSM...so I was wondering what the fix was.

Just about every car I see...the chokes are not working perfectly...but I want mine too! lol

 

[R413]

Ok. I am a pretty detailed guy...and it was set up perfectly as to the settings in the FSM...so I was wondering what the fix was.

Just about every car I see...the chokes are not working perfectly...but I want mine too! lol

You will get is set up with a few cold starts. Blowing black smoke is really bad for the rings, cylinder wear, and contaminated oil.