Hey everybody I'm Anthony an auto tech from Tucson Arizona. I look forward to getting involved with this discussion forum.

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Tony G

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Oct 28, 2023
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Location
Tucson AZ.
First Name
Anthony
Truck Year
1978
Truck Model
C10
Engine Size
4.1
I am looking for some advice in regards to a project my big mouth got me into. I am trying to put back together a 1978 C10 2wd 4.1 inline 6. Now the issue that I'm having is that the truck has had a another engine put in by another mechanic and just left this job a mess. The original engine 4.1 inline 6 had a single barrel carb with the single barrel intake and exhaust manifold. The engine that is put in there now has the o integrated style with the two barrel carburetor intake and exhaust manifold. I'm having some issues with vacuum leaks and what goes where so I thought It would just be easier to swap the head off the engine they took out and put it back to the original single barrel carb as opposed to trying to make this two-barrel work . I'm looking at time so what do you recommend I should do switch out the head and the carburetor exhaust and intake manifold or leave the two barrel in there and facilitate what it needs in order to get running because they capped off some lines wiring looks questionable and the truck won't stay running it doesn't stay running at idle I checked timing I checked firing order now I'm pretty damn sure that there are vacuum leaks but I'm not sure what goes where and now to the point of deciding which direction to go. so with that being said any information or suggestions are welcome it does have a two barrel Rochester verajet carburetor on there right now. Thank you
 
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Turbo4whl

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Location
Downingtown, PA
First Name
Wayne
Truck Year
1974
Truck Model
Jimmy
Engine Size
350
Welcome to the forum. In the reference section of this forum are some vacuum diagrams:

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I did not see a diagram for the non-integral head. The integral head could have several issues. They tend to crack, then you could have leaks. Also the carbon from the EGR valve clogs the PCV port. The carbon can block it tight.

Yes you can use the earlier non-integral head.
 

Strick

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Nov 25, 2020
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Location
Dunn, NC
First Name
Harold
Truck Year
1979
Truck Model
C20 Crew
Engine Size
350
Welcome to the site. Look around & you'll find what you're looking.

HS
 

Doppleganger

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OH-MI: Just like it sounds
First Name
Chris
Truck Year
1985
Truck Model
K20
Engine Size
5.7
Biggest vac-runability issues I always had was the carb base gasket. PO had the same issues....replaced every o-ring and gasket except that one which he obviously left just for me. What a guy.

You must be registered for see images attach
 

Travlr

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Joined
Sep 18, 2023
Posts
153
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Location
Central Utah
First Name
C
Truck Year
1978
Truck Model
K20 Camper Special
Engine Size
350
I am looking for some advice in regards to a project my big mouth got me into. I am trying to put back together a 1978 C10 2wd 4.1 inline 6. Now the issue that I'm having is that the truck has had a another engine put in by another mechanic and just left this job a mess. The original engine 4.1 inline 6 had a single barrel carb with the single barrel intake and exhaust manifold. The engine that is put in there now has the o integrated style with the two barrel carburetor intake and exhaust manifold. I'm having some issues with vacuum leaks and what goes where so I thought It would just be easier to swap the head off the engine they took out and put it back to the original single barrel carb as opposed to trying to make this two-barrel work . I'm looking at time so what do you recommend I should do switch out the head and the carburetor exhaust and intake manifold or leave the two barrel in there and facilitate what it needs in order to get running because they capped off some lines wiring looks questionable and the truck won't stay running it doesn't stay running at idle I checked timing I checked firing order now I'm pretty damn sure that there are vacuum leaks but I'm not sure what goes where and now to the point of deciding which direction to go. so with that being said any information or suggestions are welcome it does have a two barrel Rochester verajet carburetor on there right now. Thank you
Before you get started, buy a Chilton or Haynes manual for squarebody trucks.
 

Bennyt

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Joined
May 17, 2019
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981
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Location
Surprise
First Name
Ben
Truck Year
1977
Truck Model
C10
Engine Size
350
Welcome Tony! If you do determine that it is a carb issue r/t the quadrajet, there is a quadrajet shop in Peoria. Also, next month in mid November is Dino's Git Down in Glendale at Cardinals stadium. Its a good, free Chevy show. Supposedly last year there was 10,000 Chevy trucks with 3000 of them Squares.
 

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