Carb and vacuum line problems

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

Ewhitaker0020

Full Access Member
Joined
Apr 21, 2019
Posts
272
Reaction score
90
Location
Kentucky
First Name
Eric
Truck Year
1984
Truck Model
K10
Engine Size
305 5.0
I'm not saying a gen 1 small block won't run without a bunch of bits and bobs attached. They do. They'll run on liquid soap for Christ sake. Now longevity is probably a coin toss with the soap but there's a thousand ways to skin a cat.

The canister actually has a relatively simple purpose rooted in science in the fact that volatile fluids like gasoline expand and contract quite a bit from just a small difference in things like temp and air pressure. This is where the canister comes in. One line to the canister is from the gas tank so if you remove the charcoal can you still have to find a way to cap that line and you will need to source a gas cap that vents to the atmosphe at minimum. Just seems easier and possibly less mess to have a canister. Think of it like less of a smog item and more of a hey I don't have to deal with cleaning up leaking or spilled gas with this relatively unseen cylinder and it functions with my two outlet pcv so all is fine can.



The same q-jet? Hell, you have a fancy optioned truck.

I will be keeping the charcoal canister to let the gas have somewhere to expand to. Do I plug off the unused ports on the canister or let them vent to atmosphere? Also, I think my pcv valve just has one outlet.
 

DoubleDingo

Full Access Member
Joined
Jul 3, 2012
Posts
10,019
Reaction score
14,163
Location
Right where I am
First Name
Bagoomba
Truck Year
1981, 1965
Truck Model
81-C20 Silverado Camper Special-TH400-4.10s; 65-C20 with 4:57 gears and Borg Warner Overdrive
Engine Size
Carb'ed Vortec 350; 1972 L48 350
If it were me I'd run the hoses from the canister to the proper places.
 

gotyourgoat

Full Access Member
Joined
Mar 27, 2014
Posts
2,117
Reaction score
3,417
Location
NRV Virginia
First Name
gotyourgoat
Truck Year
1984
Truck Model
c10
Engine Size
smokin' 305
Ok lost light yesterday. I hope these make sense, just replaced 2 dryrotted caps for the blue ones which I believe are the egr and related ports. One would also be for power brakes(the tee I'm guessing) which I don't have.
You must be registered for see images attach
Dizzy line kinda hidden but comes out under the rusty gas line fitting.
You must be registered for see images attach

The can has 5 ports left to right in pic they are gas tank, for the center valve the larger bottom line for carb, on top of that is the pcv. Far right valve is another pcv connection from the splitter shown. Top hose goes down the frame and as far as I recall is the atmosphere vent.
 
Last edited:

Ewhitaker0020

Full Access Member
Joined
Apr 21, 2019
Posts
272
Reaction score
90
Location
Kentucky
First Name
Eric
Truck Year
1984
Truck Model
K10
Engine Size
305 5.0
If it were me I'd run the hoses from the canister to the proper places.

I will be. I just looked over the vacuum diagram and I'm going to run all the canister lines like it shows. I do have a question though. On the diagram it shows 2 tvs ports. I googled these and Google says theirth thermal vacuum switches. Does this mean they only open or close when my truck is at a certain temperature? And I saw 1 vacuum 'tree' on my water neck and one right next to it on the intake manifold. Are these the tvs's? If I'm going to have some unused ports (such as the egr valve) do I just block these ports off? One of these ports goes to my egr and egr bleed solenoid then after the solenoid it goes to the rear port of my carb. Since I won't have the egr and by relation the egr bleed solenoid would I just take that port straight to the back of my carb?

I guess a big question is do I even need my egr valve? I was planning on just blocking off the plate if I don't need it.

You must be registered for see images attach
 

Ewhitaker0020

Full Access Member
Joined
Apr 21, 2019
Posts
272
Reaction score
90
Location
Kentucky
First Name
Eric
Truck Year
1984
Truck Model
K10
Engine Size
305 5.0
Ok lost light yesterday. I hope these make sense, just replaced 2 dryrotted caps for the blue ones which I believe are the egr and related ports. One would also be for power brakes(the tee I'm guessing) which I don't have.
You must be registered for see images attach
Dizzy line kinda hidden but comes out under the rusty gas line fitting.
You must be registered for see images attach

The can has 5 ports left to right in pic they are gas tank, for the center valve the larger bottom line for carb, on top of that is the pcv. Far right valve is another pcv connection from the splitter shown. Top hose goes down the frame and as far as I recall is the atmosphere vent.

I guess my canister and carb are a little different than yours. My canister has 4 separate ports on the top of it, with the left most going to the air cleaner. Also on my carb my rear port is for the egr which I plan on deleting.

I don't see one on my canister that vents to the atmosphere. It might be the one that goes to my air cleaner since that probably burns the gas fumes from the canister.

You must be registered for see images attach


You must be registered for see images attach
 

DoubleDingo

Full Access Member
Joined
Jul 3, 2012
Posts
10,019
Reaction score
14,163
Location
Right where I am
First Name
Bagoomba
Truck Year
1981, 1965
Truck Model
81-C20 Silverado Camper Special-TH400-4.10s; 65-C20 with 4:57 gears and Borg Warner Overdrive
Engine Size
Carb'ed Vortec 350; 1972 L48 350
I've asked similar questions about what those things are but never got an answer. I think you are correct on how it works, though. Your canister doesn't seem to match the sticker, or the air cleaner is different. My canister looks like the clean one @gotyourgoat posted up.
 

Ewhitaker0020

Full Access Member
Joined
Apr 21, 2019
Posts
272
Reaction score
90
Location
Kentucky
First Name
Eric
Truck Year
1984
Truck Model
K10
Engine Size
305 5.0
I've asked similar questions about what those things are but never got an answer. I think you are correct on how it works, though. Your canister doesn't seem to match the sticker, or the air cleaner is different. My canister looks like the clean one @gotyourgoat posted up.


My canister looks just like my sticker. 4 separate ports with the 2 on the right having an extra port on top of each.
 

gotyourgoat

Full Access Member
Joined
Mar 27, 2014
Posts
2,117
Reaction score
3,417
Location
NRV Virginia
First Name
gotyourgoat
Truck Year
1984
Truck Model
c10
Engine Size
smokin' 305
For reference this is the original unit I replaced a couple weeks ago. There is usually some variety of little vent/airlock thing (which does not have a hose connected to it) next to the gas tank port. Where the hole is on the right in this pic
You must be registered for see images attach
 

Ewhitaker0020

Full Access Member
Joined
Apr 21, 2019
Posts
272
Reaction score
90
Location
Kentucky
First Name
Eric
Truck Year
1984
Truck Model
K10
Engine Size
305 5.0
For reference this is the original unit I replaced a couple weeks ago. There is usually some variety of little vent/airlock thing (which does not have a hose connected to it) next to the gas tank port. Where the hole is on the right in this pic
You must be registered for see images attach


I don't see one on mine. Maybe on mine it's the one that goes to the air cleaner. Where you have a hole I have another port and the vacuum diagram says it goes to the air cleaner.
 

DoubleDingo

Full Access Member
Joined
Jul 3, 2012
Posts
10,019
Reaction score
14,163
Location
Right where I am
First Name
Bagoomba
Truck Year
1981, 1965
Truck Model
81-C20 Silverado Camper Special-TH400-4.10s; 65-C20 with 4:57 gears and Borg Warner Overdrive
Engine Size
Carb'ed Vortec 350; 1972 L48 350
My canister looks just like my sticker. 4 separate ports with the 2 on the right having an extra port on top of each.

I had to go back and look again. With all the dirt on top the bottom ports look to be non-existent.
 

Ewhitaker0020

Full Access Member
Joined
Apr 21, 2019
Posts
272
Reaction score
90
Location
Kentucky
First Name
Eric
Truck Year
1984
Truck Model
K10
Engine Size
305 5.0
I had to go back and look again. With all the dirt on top the bottom ports look to be non-existent.

What are you trying to say?? Do you think my canister is dirty? I've got a lot of work to do to this truck before I get it back on the road again. What's this transmission cable I keep hearing about people adjusting.
 

DoubleDingo

Full Access Member
Joined
Jul 3, 2012
Posts
10,019
Reaction score
14,163
Location
Right where I am
First Name
Bagoomba
Truck Year
1981, 1965
Truck Model
81-C20 Silverado Camper Special-TH400-4.10s; 65-C20 with 4:57 gears and Borg Warner Overdrive
Engine Size
Carb'ed Vortec 350; 1972 L48 350
You're on the right track, and all that you're doing will make it run way better than it was. I don't have a trans cable so I'll let others answer that one.
 

gotyourgoat

Full Access Member
Joined
Mar 27, 2014
Posts
2,117
Reaction score
3,417
Location
NRV Virginia
First Name
gotyourgoat
Truck Year
1984
Truck Model
c10
Engine Size
smokin' 305
My sticker has so much over spray on it the thing is pretty useless. The line on the can I labeled vent is incorrect. My previous owner removed the egr. It is the purge signal hose (which goes to the egr) in your label. Not sure where I'd even hook that line up to at this point.
 

DoubleDingo

Full Access Member
Joined
Jul 3, 2012
Posts
10,019
Reaction score
14,163
Location
Right where I am
First Name
Bagoomba
Truck Year
1981, 1965
Truck Model
81-C20 Silverado Camper Special-TH400-4.10s; 65-C20 with 4:57 gears and Borg Warner Overdrive
Engine Size
Carb'ed Vortec 350; 1972 L48 350
This is a setup with no EGR, no CAT(s), just the A.I.R. stuff, and there is no lack of power whatsoever with the A.I.R. stuff hooked up. I know your A.I.R. stuff is coming off, just letting you know it doesn't rob any power from the engine.

You must be registered for see images attach
 

Ewhitaker0020

Full Access Member
Joined
Apr 21, 2019
Posts
272
Reaction score
90
Location
Kentucky
First Name
Eric
Truck Year
1984
Truck Model
K10
Engine Size
305 5.0
This is a setup with no EGR, no CAT(s), just the A.I.R. stuff, and there is no lack of power whatsoever with the A.I.R. stuff hooked up. I know your A.I.R. stuff is coming off, just letting you know it doesn't rob any power from the engine.

You must be registered for see images attach


Honestly, it's really just an asthetics thing at this point the tubes off of the exhaust manifold are obtrusive and ugly. I'm thinking about installing some plugs into the holes if I can even remove the tubes, they're pretty rusty. If they give me trouble I'll just leave them on there.
 

Latest posts

Forum statistics

Threads
41,854
Posts
903,565
Members
33,367
Latest member
texdave
Top