AVS Choke Doesn't Work

[Franko]

I am reposting this thread with a more accurate Title. It ended up being added to a question about a Thermoquad ID.

Last month I bought a 69 Dart Swinger in which almost everything is correct except the 71 340 engine and 71 360 heads. The carb is the correct Carter AVS No, 4611S. I was considering buying a Thermoquad because I can’t get the choke to work. Also a guy in a carb shop told me the AVS didn’t operate well with today’s gasoline, didn’t tune well and was costly to buy metering rods. Another guy told me they were fine carbs. I would prefer to run the AVS for correctness.

When I purchased the car it was really hard starting. It turned out the choke is always stuck wide open. The spring seems fine, but the linkage binds in the choke well. And the linkage is too long even though it was bent. It had the correct 45 stamped on it. I ordered a new one with the same result. So I ordered an original one from Tony’s- same result. When I disconnect the choke linkage, the butterfly does not bind. I’ve talked with 3 carb shops and they didn’t know anything about this issue.

It doesn’t seem like the linkage angle will work with the butterfly arm which has swung past the low point (it’s hard to explain). The arm needs to be pushed toward the rear first, past the low point, then up, to work properly. I’ve read prior posts. Even though some members have mentioned some AVS choke issues, I never could determine a resolution that would help me.

Does anybody have any knowledge of this issue and know the way to fix it? It doesn’t seem like an electric choke can be installed, from what I’ve read.

 

[fanofpetty]

what intake manifold are you using this AVS on? Is it the correct 69 340 intake?

 

[RedFish]

Any time we put a different spacer under the carb we have to alter the length of the choke rod. Changing the length means changes in the angles.
Could be you have the wrong spacer. A very thin one will do just what you describe. A thick spacer will only improve everything including fuel temp in the bowl.

 

[Franko]

Good questions. My intake manifold No. is 2531915. I appears to be the 1968 340 intake. The number I found for a 68-71 intake is 2531914. I found these on http://www.mymopar.com/intakecastnumb.htm. I asked the guy I purchased the car from and he thought the 68 manifold would have been used on the 69. When he bought the car it didn't have an engine, so he bought this intake and carb at a junk yard.

It has a thin gasket. I asked a carb shop and they said this is correct. I also held up the carb a little and it didn't seem to make a difference.

I am really stuck- kind of like that pesky linkage.

 

[RedFish]

If my memory serves correct the parts guy found the thicker base gasket listed under 75 model E-body. Even if a thicker gasket doesn't completely cure the choke linkage issue, it is a vast improvement for cold start, hot restart, etc..
Can you post pics of what you have ?

 

[mcodecuda]

Can you post a picture of the choke well side of the carb and manifold?

 

[rumblefish360]

Do you have the OE "Thick" gasket under it or the thin paper one?
You need the thick gasket and the electric assist working for a TQ to work right.

Otherwise, a pull cable will work and look ugly.

 

[Franko]

Here's some pictures of both sides of the carb showing the linkages with the butterfly open and closed.

 

[mcodecuda]

Take the linlage rod thats on the throttle linkage side of the carb and reverse it. I'm not sure if that will fix your issue but right now its upside down.

 

[67Dart273]

First thing I'd do is disconnect the thermostat and make sure the linkage on the carb is working freely

To do that, disconnect the thermostat, and while holding gently against the choke butterfly, opent the throttle slightly, at which time you should be able to push the butterfly completely closed with no effort.

RELEASE the throttle, which should bring the throttle down on the fast idle step. You should now be able to push the choke easily closed, and when you open the throttle slightly, the weight of the fast idle cam should pull the choke butterfly completely open.

All this should work freely and easily, with no help from your fingers.

Next, maybe with a second person, hold the choke closed and start the engine, without dropping the throttle off the fast step. The choke pull-off diaphragm should now suck inwards, and this should make a definate "stop" which you cannot push the choke butterfly past. That is, the pull off sucks down and opens the throttle butterfly by some amount, the specs of which are in the shop manul.

If all that checks out, you can then concentrate on the choke thermostat.