Quadrajet question
 

Have a quadrajet on a 72. The front vacuum port is plugged which I understand to be normal. It has one on the passenger side near the choke setup that is open and not capped. What is this supposed to go to or should it be capped? Here’s a pic.

Re: Quadrajet question
 

It's called a diverter port. I have no idea what it would be used for, but I think it has vacuum at idle. Mine is capped.

Re: Quadrajet question
 

Charcoal canister full time manifold vacuum port.

Re: Quadrajet question
 

The one on the side of the carb is a manifold vacuum source for the air cleaner Thermac snorkel valve.

If you are looking for the utmost correct look, the TCS emission control system is missing, and it appears the lines to the charcoal canister are gone.

https://67-72chevytrucks.com/vboard/...1&d=1647035907

Re: Quadrajet question
 

My quadrajet has a canister purge port on the front. It is ported vacuum. Anytime engine is off idle it activates the switch at the canister which in turns allows the canister pcv port to open and dump the fumes into the pcv port at the carb through a tee. I changed my old canister and added an external switch. New ones don't have it built in and it works great. No more gas fumes.

Re: Quadrajet question
 

Not sure why anyone would want a TCS system and I understand why people would remove them and throw them away. They seem like a PITA. Bet a complete working system is super hard to find today.

What did it all look like originally and where did the charcoal canister mount? Did all the 72s come with them?

For now I'm going to cap it off.

Re: Quadrajet question
 

Canister next to and below the battery. They were an answer to non-vented fuel tanks. The charcoal absorbed the fuel vapors instead of venting out the cap. My 72 is a C10 and I may be wrong, but I believe only 1/2 tons had the canister and smog setup that year. Someone will know for sure.

Re: Quadrajet question
 

You do realize that you can have the solenoid present, and all hooked up, and vacuum can pass through it as long as it is not electrically energized...

Re: Quadrajet question
 

https://67-72chevytrucks.com/vboard/...1&d=1610814910

https://67-72chevytrucks.com/vboard/...1&d=1673469394

https://67-72chevytrucks.com/vboard/...1&d=1673469375

Re: Quadrajet question
 

Actually you get no vacuum thru it until you’re in high gear.

Re: Quadrajet question
 

I'm not talking about an actual original functional system. I am referring to a "for appearances only" system. Verified with a hand vacuum pump/gauge, the solenoid on my 1970 allows vacuum through it when the system has had it's power source rendered inoperable. It looks 100 percent correct and allows full vacuum to the distributor advance can at all times when there is manifold vacuum available.

Re: Quadrajet question
 

I do now. I would like a completely factory stock appearing but non-functional setup, but not sure what all would be needed. Components underneath the truck probably don't matter. Would just need the pieces for the system that are visible underhood.

Re: Quadrajet question
 

Keep it functional and just hook the wire on the trans to a good ground.

Re: Quadrajet question
 

Interesting! Yours allows vacuum thru it.
Do you have a pic of yours so I can see where the vac lines go.

Re: Quadrajet question
 

Re: Quadrajet question
 

The 1972 350 solenoid is DR1114451 or just 1114451.

Re: Quadrajet question
 

Lookee there!
A solenoid deep in the shadow with no indication of how the vac hoses are connected to it.

Re: Quadrajet question
 

That's all you are getting. It's very plain to see from where I am sitting.:waah:

Re: Quadrajet question
 

Typical!

Re: Quadrajet question
 

This message is hidden because geezer#99 is on your ignore list.

Re: Quadrajet question
 

C’mon!
You can do better than that!

Re: Quadrajet question
 

So all I would need is said solenoid the mounting bracket bolt and a couple of vacuum lines?

Re: Quadrajet question
 

If you don't have the repair manual for your truck, you can get one here for free download. I don't have this system on my truck, since it's a 3/4T. But this manual will show it.
https://67-72chevytrucks.com/vboard/...ghlight=hatzie