Help bringing this K20 back to life..

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Ajax19

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It’s high idle. Stays on as long as fuel in the container. These two ports on intake uncapped.
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Those are for the factory choke
 

Ajax19

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It is switched to left, but I just watched a video where a guy with a square body ended up checking everything with fuel system because he couldn't get gas to tank either and after all electrical tests came back normal, it ended up being the switch in the cab.

I guess I didn't understand what you meant earlier. When it was high idle, I plugged the two intake ports that I had shown in the pic and had the brake booster, vacuum advance and pcv all connected.

I don't have an air compressor, but I can get one, since I'll need one to do the media blasting on this truck anyway. The fuel from the tank was evaporated. I was going to syphon the gas out of the tank and put fresh fuel, but there was nothing in it. Maybe it evaporated because right side fuel tank was uncapped? I put four gallons in the tank at that point.
So, the feed line and the return line are still both disconnected from the fuel pump. I disconnect the vapor hose at pump and run air through it, looking for gas to go in bucket from feed line?
Bypass the tank switching valve it's probably all gunked up inside
 

Dano500

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Bypass the tank switching valve it's probably all gunked up inside
I see, I plugged both ports up on the intake and it helped. Truck runs fine now, out of the can.

I'm new to all of this, so do you mind my asking how I bypass the valve?
 

Ajax19

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I see, I plugged both ports up on the intake and it helped. Truck runs fine now, out of the can.

I'm new to all of this, so do you mind my asking how I bypass the valve?
Passenger side frame rail at the back of the cab trace the fuel lines from the tank to the valve pop the lines off the valve from the tank your going to use for testing and hook them up to the steel lines running up front
 

Dano500

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Passenger side frame rail at the back of the cab trace the fuel lines from the tank to the valve pop the lines off the valve from the tank your going to use for testing and hook them up to the steel lines running up front.
I did it and now it won’t run. Even blew out both feed and return lines. The driver side tank was empty when I first went to syphon and I did notice the passenger gas cap was missing when I first started working on it. Would I go to sending unit at this point?
 

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Ajax19

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Could be the sending unit rusted away if it runs off the bottle and lines are clear and fuel pumps good only thing I think it could be not getting fuel from the tank I have a electric lift pump so maybe it needs to prime try squirting a little fuel down the carb to help it prime
 

Dano500

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Yeah, I should have mentioned that. I did prime it with gas and it ran a few seconds and it just died a few seconds later.

The vacuum line was cut from valve, so maybe last owner tried to disable valve, but it was sender. Idk
 

Dano500

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Could be the sending unit rusted away if it runs off the bottle and lines are clear and fuel pumps good only thing I think it could be not getting fuel from the tank I have a electric lift pump so maybe it needs to prime try squirting a little fuel down the carb to help it prime
Boy was it all rusted. lol
 

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