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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idahovette

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OP hasn't been around since the first post?? And it's a 6 cylinder with a varijet 2 barrel or possibly a 1 barrel.....I'm confused???????
 

Turbo4whl

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OP hasn't been around since the first post?? And it's a 6 cylinder with a varijet 2 barrel or possibly a 1 barrel.....I'm confused???????


He was here today at 1:30 PM. He also thanked me with a private message for the vacuum diagrams.
 

Tony G

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Anthony
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I will be posting pics later this evening
 

Tony G

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I'm still learning how to reply I was using the start conversation to reply. Now I see at the bottom of my msg list is the reply box.
 

Tony G

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It's an inline 6 4.1 with the 2barrel Rochester varajet carb and I wanted to put the original 1barrel back on because I'm not sure what goes where in regards to the EGR plumbing and vacuum lines go. The guy who installed the engine left it undone and a mess. Also I'm not sure where the adjustment is for fuel and air on this 2 barrel varajet carb
 

Turbo4whl

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It's an inline 6 4.1 with the 2barrel Rochester varajet carb and I wanted to put the original 1barrel back on because I'm not sure what goes where in regards to the EGR plumbing and vacuum lines go. The guy who installed the engine left it undone and a mess. Also I'm not sure where the adjustment is for fuel and air on this 2 barrel varajet carb
There is a good chance the 2 barrel has sealed mixture screws, that is why you don't see them. A mini plug covers the screw. You can remove the plug with a small hole saw tool, also hard to do correctly. Then the screw inside is not a slotted screw, you need another special driver/socket. Looks like a double "D".
 

Tony G

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C10
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4.1
I know the tool that you speak of I was actually trying on a area on the carburetor not prime but digging into where I thought the adjustment mixer screw was and it just seemed like if I was doing too much work so I just sealed it back up before I went too deep now I was probably in the right spot but then again I didn't want to damage something to the point where I had to get a new carburetor or whatnot so I'm going to send some pictures out right now
 

Tony G

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C10
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4.1
Here are the picture sorry so late but I only work on it when I can
 

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Tony G

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Tucson AZ.
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Anthony
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1978
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C10
Engine Size
4.1
Now according to the owner the previous mechanic cut off some theme from the valve covers that it looks to me hold PCV valves or check valves and run back into the intake or run back into the valve cover I'm not really sure but the lady said that he said that they didn't need them anymore and I don't know exactly where to start after that so if I need another valve cover or am I able to work with what is if you need some more pictures I just barely got here so I'm going to start getting my hands dirty in a little bit
 

pinballlarry1

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I just recent valve job on my '81 C10 with the same engine and set up.
this is my vacuum diagram:
You must be registered for see images attach



This picture of yours shows a large vent line going from the fuel bowl, around to the canister vent purge inlet on the carb base:
You must be registered for see images attach

Remove immediately, that is not the proper routing. This allows a lot of extra air to be sucked out of the fuel bowl vent directly into the intake manifold. This is probably killing the engine at idle. Route the two large hoses to the vapor canister by the radiator.
 
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Ricko1966

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Okay deleting all these things is not good advice,it also is illegal although the chances of getting caught are slim,but the fines are big,that's gotta be fun. I don't know why people think exempt from testing is the same as legal to remove. The police aren't going to come in your house and inventory your guns. Just because the police aren't going to inventory your guns,doesn't mean it's legal to modify them for full auto. Big difference between no inspection and legal. You're egr allows you to run more timing for more mpg , also partial chamber filling with inert gas for more mpg and less preignition chances,and also cooler cylinder temperatures.The Evap system keeps your fuel from evaporating so you get to burn all of it, instead of some of it while the rest evaporates,also since it keeps the system sealed you don't get as much water vapor in the gas tank.. The efe heats the intake when it's cold to aid cold weather drivability ,and a hot intake gets better mpg. The pcv keeps oil leaks down and helps ring seal,for more power and mpg. The hot air door on the air cleaner again hot air on coldstarts for better cold weather driveabilty,hot air makes more mpg than cold air,these are all scientifically proven. And last but not least warm intake from efe,warm carbureator from hot air,the choke can open sooner,again more mpg and less fuel wash on the cylinders.
 
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Camar068

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10 yrs Air Force
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
Welcome!

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Hogger

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Welcome from Benson, just down the road.
 

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