Choke coolant line?
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I assume the 65 is like the 66. The round black cap on the carb houses the choke coil. There should be a metal clip that holds one of the heater hoses against it to aid in the heating of the coil. THis clip is also what holds the housing cover on and is how its adjusted. The main way the choke is operated is a small metal line from the nipple on the side of the housing down to a hole in the exhaust manifold. That hole is supposed to be a tube that runs through the 3&4 port so the fresh air is heated as its drawn past hot exhaust flow. Often times a leaky gasket or cracked manifold lets exhaust gas get drawn into the choke. This eats that tube up, sizes the nipple on the housing, melts the plastic coil housing, plugs up the choke vacuum port along with several other passages in the carb. On mine I had to use a drill bit to open some of them because the carbon was packed in so hard.
Here are some photos I made for other reasons but they show the common issues and that clip that holds the hose.
Here are some photos I made for other reasons but they show the common issues and that clip that holds the hose.
There was a later version of one of the I6 carbs that instead of the black housing it had a large metal housing with two 5/8 nipples for the heater hoses to actually connect to. I dont think this model had the exhaust port on it. The later electrical ones (or converted to electrical) had a different cap on them with an electrical terminal. You can also buy a kit that converts the black cap to an arm for a manual cable. They are designed for V8's so mounting the cable can be a pain and require some fab work, also they dont work like a true manual choke because you have to step on the gas as you pull the lever to get it to 'set' properly.
This is what it looks like from the other side. The line to the choke pulloff is an aftermarket item. The stock configuration was a hot air tube that ran from a hole in the exhaust manifold to the pulloff cap.
The coolant lines run to the spacer/warmer plate between the carb and the intake manifold. I do not have them connected. The heated water runs straight to the heater core.
In a later configuration, one of the heater/coolant lines ran past the pulloff cap, secured by a clip. This was to keep the heat up. There are also other hot water choke pulloffs that do use coolant. We don't see much of these. Use the electric, hot air or manual.
The coolant lines run to the spacer/warmer plate between the carb and the intake manifold. I do not have them connected. The heated water runs straight to the heater core.
In a later configuration, one of the heater/coolant lines ran past the pulloff cap, secured by a clip. This was to keep the heat up. There are also other hot water choke pulloffs that do use coolant. We don't see much of these. Use the electric, hot air or manual.
That is the hot air tube for the choke, It connects to the hole in the factory exhauct manifold that has a circle around it in the photos above. It is on top of manifold... It slides in the hole. The white wrapping around tube is a heat resistant wrapping. Since you have headers, they have an adapter that clamps on the header tube that has an attachment for the hot air tube to slide in and pick up heat from it to go to the carb's choke assembly. Or you can convert it to an electric choke provided that they have a kit for your carb and forget the hot air choke setup...
Adding to the correct info above: There is a small hole in the carb inside the choke pulloff device. When vacuum is made is made in the carb, the tube pulls air from a port in the exhaust manifold through the tube to a bimetal coil spring inside the black cap. As the manifold gets hotter, the air heats up, causing the spring to move and this is what actually pulls the choke off.
Most stock manifolds look like the burnt cinder between ports 3 and 4 that you can see in the pic above. When this happens, you are pulling exhaust into the choke and the carb. If the hole is big enough, the exhaust pressure actually PUSHES exhaust into the cap area. This can melt the cap, fill the area with soot and plug the small hole to the carb, all leading to choke failure.
The solutions are to clean up the choke pulloff mechanism and replace the choke tube with that little aftermarket set I have that clamps on the OUTSIDE of the exhaust manifold or to get an electric or manual choke.
Most stock manifolds look like the burnt cinder between ports 3 and 4 that you can see in the pic above. When this happens, you are pulling exhaust into the choke and the carb. If the hole is big enough, the exhaust pressure actually PUSHES exhaust into the cap area. This can melt the cap, fill the area with soot and plug the small hole to the carb, all leading to choke failure.
The solutions are to clean up the choke pulloff mechanism and replace the choke tube with that little aftermarket set I have that clamps on the OUTSIDE of the exhaust manifold or to get an electric or manual choke.
Don't worry. We've all been there. Some of us still are there. As one of Werner von Braun's engineers said about the start of the Atlas/Redstone rocket project: "Vell, ve had a lot of failures at zat time. But zat is a good ssing. Because if you succeed ze very first time, you don't learn anyssing."
It's called a 'choke pulloff tube'. You can get the aftermarket thing separately. I think they called it a choke 'pulloff tube and stove'. They just happened to have one at the speed shop I went to. The stock configuration has just the tube secured with the brass fitting on one end and simply stuck (i.e. interference fitting) at the manifold.
You could get by without the stove part by just wrapping some soft alu tubing three or four times around the manifold. As long as it gets hot and air goes through.
You could get by without the stove part by just wrapping some soft alu tubing three or four times around the manifold. As long as it gets hot and air goes through.
This is the stuff most stores carry under the 'HELP' name, some stores have their own name on it like Napa balkamp. Either way the part numbers should cross to something they do stock carry.
https://www.dormanproducts.com/cgi-bin/ ... time=33153
When I was thinking of going electric this was the one that I thought would work but never verified it would physically fit.
http://www.napaonline.com/MasterPages/N ... -+Integral
https://www.dormanproducts.com/cgi-bin/ ... time=33153
When I was thinking of going electric this was the one that I thought would work but never verified it would physically fit.
http://www.napaonline.com/MasterPages/N ... -+Integral
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