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Discussion Starter · #1 ·
I'm having a problem and can't figure it out. My carb idles fine but my high idle cam is sticking. When the carbs cold and I hit the gas pedal the choke doesn't close. if I leave the choke in the center of the rich/ lean mark. If I turn the choke far back to the left which tightens the spring, it works but it's then far off any of the choke reference marks. If I take the carb off the intake and push the fast idle cam lever down and lock it, then flip the gas, it will close easy and with no binding. Don't know what to do. Any advice?
 

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Unfortunatly your pictures don’t show what we need to see which is this an electrically heated model in which case there will be one or two electrical wires depending on how it’s grounded. Or is a a hot air heated in which case it will have a hose connection to the exhaust heat crossover passage of the intake manifold or possibly to the exhaust manifold.

The test is fire the engine up and test the plastic cover for getting hot. Either electricity heated or hot air will get that cover pretty warm after a few minutes running. If that doesn’t happen then you’ll have to fix whatever this one is using as a heat source.

Electrical you have to test the connections for power when the engine is fired up. If there’s power but no heat then the choke spring is shot and will need replacing. These are unique to electric chokes a spring assembly for a hot air is unlikely to work properly.

The hot air system uses a tube off the intake exhaust heat crossover. but sometimes these are in the exhaust manifold ya got look around. This does not pull exhaust into the choke thermostat. There is an open end of a tube to atmosphere somewhere it usually has a filter or is connected to the factory air cleaner. There is a small vacuum leak port on the side of the carb. This is connected to the choke’s thermostat housing, it pulls air into and through the exhaust heated tube (often referred to as the “choke stove”) into the choke housing with the thermostatic spring. This whole little air bleed system needs to be working or the choke doesn’t except for what you’re seeing by cranking on the spring tension, but without heat it doesn’t change on its own it just sits where you last left it. If the tube has failed and the choke is pulling exhaust gasses you will find the inside of the cover badly damaged and in need of replacement.

Bogie
 

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Discussion Starter · #3 ·
Unfortunatly your pictures don’t show what we need to see which is this an electrically heated model in which case there will be one or two electrical wires depending on how it’s grounded. Or is a a hot air heated in which case it will have a hose connection to the exhaust heat crossover passage of the intake manifold or possibly to the exhaust manifold.

The test is fire the engine up and test the plastic cover for getting hot. Either electricity heated or hot air will get that cover pretty warm after a few minutes running. If that doesn’t happen then you’ll have to fix whatever this one is using as a heat source.

Electrical you have to test the connections for power when the engine is fired up. If there’s power but no heat then the choke spring is shot and will need replacing. These are unique to electric chokes a spring assembly for a hot air is unlikely to work properly.

The hot air system uses a tube off the intake exhaust heat crossover. but sometimes these are in the exhaust manifold ya got look around. This does not pull exhaust into the choke thermostat. There is an open end of a tube to atmosphere somewhere it usually has a filter or is connected to the factory air cleaner. There is a small vacuum leak port on the side of the carb. This is connected to the choke’s thermostat housing, it pulls air into and through the exhaust heated tube (often referred to as the “choke stove”) into the choke housing with the thermostatic spring. This whole little air bleed system needs to be working or the choke doesn’t except for what you’re seeing by cranking on the spring tension, but without heat it doesn’t change on its own it just sits where you last left it. If the tube has failed and the choke is pulling exhaust gasses you will find the inside of the cover badly damaged and in need of replacement.

Bogie
Thanks for responding. It's a new electric choke with a power wire and sensor. The problem is that the fast idle cam lever that goes up when choke is closed and down when it's open will open freely when disconnected from the choke lever. But won't shut closed when I open the throttle to release the cam unless I turn the chokes plastic cover counter clockwise past the marks on the choke. If you look at the black cover of the choke, there is a white dot that sits at 1200 on the rich to lean marks. At that position the spring won't snap the choke closed. If I turn it counter clockwise it Snape's the choke closed as it should because the spring pressure is stronger.
 

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Discussion Starter · #4 ·
Thanks for responding. It's a new electric choke with a power wire and sensor. The problem is that the fast idle cam lever that goes up when choke is closed and down when it's open will open freely when disconnected from the choke lever. But won't shut closed when I open the throttle to release the cam unless I turn the chokes plastic cover counter clockwise past the marks on the choke. If you look at the black cover of the choke, there is a white dot that sits at 1200 on the rich to lean marks. At that position the spring won't snap the choke closed. If I turn it counter clockwise it Snape's the choke closed as it should because the spring pressure is stronger. At that point it's not on any of the marks for the lean rich indicators
 

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Normally those electric choke kits are mounted on the intake bolts with a rod that reaches up to connect onto the linkage.
your carb is an original divorced choke type. Likely one of the very early ones. Near to 1966-67. The secondary lock out tells the tale to originality.
Maybe the linkage rod on the back of the black coil assembly is binding up.
 

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Discussion Starter · #6 ·
Normally those electric choke kits are mounted on the intake bolts with a rod that reaches up to connect onto the linkage.
your carb is an original divorced choke type. Likely one of the very early ones. Near to 1966-67. The secondary lock out tells the tale to originality.
Maybe the linkage rod on the back of the black coil assembly is binding up.
Thanks for responding. I took the choke kit off and it moves freely just like the linkages on the carb. It seams the spring needs a little more tension from the spring inside the black cap and then it works. Unfortunately it's way past rich at that point
 

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Don’t rely on the marks on the cap. I’ve found they’re normally not accurate.
‘Just set it wherever works best.
 

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Disregard my post I can’t delete it, after looking at photos again RWENUT is spot on about carb age and style. I was thinking you had 70 or newer style but cliff ruggles is still a great source.

Here’s a quick note, the choke housings were not all the same depth and the lever arm in side also had a different lengths. My quick thought is your electric choke kit is not correct one for your carb. I have seen where the lever arm finger does not index into the square of the spring. Instead the front edge of the spring square on choke, just touch’s the front of the choke lever arm. When loose it seems to work as you adjust choke but when you tighten the 3 screws the spring and choke arm bind.

Measure from the choke housing seating face to the lever arm. Then measure from electric choke face to front edge of spring.

My hope is that you will find both dimensions very close to each other, thus confirming the binding issue.

I would then email cliff ruggles and give him your carb part number, tell him you need electric choke for carb and buy part for him. Reason I say to talk with cliff is do to all the different choke housing, he knows them by heart

Good luck
 

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What are everyone's thoughts concerning THIS thought:

FT mentioned that when he takes the carb OFF the intake, the choke seems, travel- wise at least, to move properly. Can we run 12V to the choke, with the carb off the intake, to see if the choke functions as it should? Should take 2-3 mins?

Also, do you know what part # was the choke conversion kit you used? And where did you buy it from?
 

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Well you could just ignor the reference marks and set the tension where it works.

It looks like the reference mark is just paint on a serrated edge. In this age of manufactures putting quantity ahead of quality, and most of this stuff being made in a Chinese barn who knows if any attempt of accuracy was tested against actual function. Just put it where it works and drop a new blob of paint on it so you know where the magic spot is.

Bogie
 
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