djrasras

Hey guys, so I took off my carb to get it rebuilt, and like an idiot, I didn't take pics of how it looked before, and I am having a lot of trouble getting everything put back on. I'll start first with the vacuum hoses. I am trying to follow the following diagram

Here is a close up of my carb

My first question is, what goes into the connection at #3? I am guessing it connects to the heater core somehow, since there is a tube/pipe missing in the heater-core plate, which can be seen in a picture I'll be inserting below. I'm also wondering if I have the #2 hose setup properly, as it looks like it is where "D" is in the first diagram (looks like the diagram just shifted the location a bit for clarity maybe).

Now here is a picture showing the rear of the carb


I am guessing I have to connect the #2 pipe from the heater plate to the rear of the carb at connection #1 somehow. Please correct me if I am wrong. This picture also shows how there is a pipe/tube missing at #3, which I explained earlier above. I am guessing this has to the choke somehow, but as you can see, connection #4 already has a hose connected to it, which you can see a little better in the first picture.

So here is what I have so far, any help would be appreciated. I just want to know if anything I have connected already is wrong, and how to move forward with the stuff that isn't connected.

68blvert

#2 from the thermal switch goes to port "D"(#3 in first pic) on your diagram. the steel pipe(#2 in second pic) goes to the hot air choke(#4 in second pic). the pipe out back of carb(#1 in second pic) goes to thermal switch in air cleaner housing base

djrasras

Thank you so much. I figured this is how it should go, however the #2 hose is too big to fit on to port #3, which is why I connected it to the hot air choke, which it fits on perfectly. I guess the solution would be to replace the #2 hose with a smaller one, however it doesn't seem to one to slide off of the thermal switch (its connected as if its a part of it). That's where I am confused.

As for the #2 steel pipe, I am guessing I have to connect it to the hot air choke with some kind of tubing as well?

lars

That's not correct.
#1 in second pic is the air supply for the hot air choke heat exchanger in the manifold. It takes a steel tube from this location to the air inlet hole in the intake crossover.

Lars

lars

All your choke cover screws are loose - have you changed the choke setting since I set it? If so, why..?

Lars

bmotojoe

The metal hot air choke setup, and the type of hose to connect the hot air choke to the tube would be 1/4" silicone hose. Standard rubber hose will not last long. This picture if from my 77 essentially the same setup.

djrasras

Hey Lars, figured you would probably find this thread
First off, thanks again for the awesome work, really excited to see how the car runs after I get this installed correctly. No I haven't messed with the choke at all, I took this pic right after I bolted in the carb and started messing with the hoses. I actually just learned how a hot-air choke even works so I don't trust myself to do any adjustments yet (or ever lol). I'll tighten those screws though, no idea how they got loose.

I guess the pipe in the second pic is the one that goes from the exchanger to the choke, meaning I'm missing the one that goes from the carb to the heat exchanger. Anyone know where I can get this part for cheap? A couple sites are charging around $40 for it -__- I'll try to find it in the meantime

Lastly, if hose #2 in my first pic won't fit into port #3 for whatever reason (I know that the last owner of this car did a bit of messing around under the hood), I guess I'll just cut it halfway and couple it with a hose that fits.

68blvert

oops. thats what i get for not looking close enough. sorry about that

djrasras

no worries, waiting on some hoses and tubes, and hopefully thing thing will be running smooth real soon! I also saw a thread that Lars was participating in regarding a lot of c3s needing accelerator cable adjusting, I'm gonna look into that since I have felt like the car has never been hitting full throttle with the pedal pressed down all the way

bigvette1

Just kind of a SA reply. With all those vacuum hoses I am surprised the car runs at all and has enough vacuum to open the headlights. What a design GM worked up