Help bringing this K20 back to life..

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Dano500

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Yes, I don’t notice any misfires, but I think she is burning some oil. No leaks so far underneath.
 

Ricko1966

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Do you have an air compressor?
 

Dano500

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No, do I need one to blow out the line? I wonder how often does the switch to go from left to right tanks goes bad.

The right tank didn’t even have a gas cap on it.
 
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Ricko1966

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Is it switched to right tank or left tank? Do have a buddy that can bring over an air compressor? What I want you to try to do us plug the vent hose at the front not real well but plugged. Put a piece of fuel line from the fuel line on the truck frame down into a bucket. Now take a shop towel and some compressed air,use the shop towel and your hand as a gasket try to put some pressure to the tank,not a bunch, just pressure. Does fuel run into the bucket? What does it look like what does it smell like. Now go under the truck.look for wet spots on any of the rubber hose or metal line. I'm seeing if you're sucking air if so it won't pick up fuel. I'm also trying to stop you from blowing out a line and the hooking things up and sucking a bunch of crap and bad gas into your fuel pump,filter if there is one,and/ your carureator,If your bored you can start hooking up vacuum lines run it on the gas can,don't do all of them at once.So if it quits running right we know it's from whatever line you just hooked up.
 
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Ricko1966

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Running on the can first hook up the brake booster, run the truck,still runs good? Carry on. You see what we are doing?
 

GTX63

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Yes, I don’t notice any misfires, but I think she is burning some oil. No leaks so far underneath.

Smoke isn't uncommon for trucks that have been sitting for a few years. Rings stick, valve seals dry out.
Driving them/putting miles on the motors once the truck is roadworthy can many times help. Products like seafoam, Berryman B12, Marvel Mystery Oil, etc can also help.
 

Dano500

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Smoke isn't uncommon for trucks that have been sitting for a few years. Rings stick, valve seals dry out.
Driving them/putting miles on the motors once the truck is roadworthy can many times help. Products like seafoam, Berryman B12, Marvel Mystery Oil, etc can also help.
Yeah, I noticed that, thank you. As I drove it around the yard and let it idle for a long time, the smoking slowly stopped. I’m still going to add one of those additives though.
 

Dano500

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Is it switched to right tank or left tank? Do have a buddy that can bring over an air compressor? What I want you to try to do us plug the vent hose at the front not real well but plugged. Put a piece of fuel line from the fuel line on the truck frame down into a bucket. Now take a shop towel and some compressed air,use the shop towel and your hand as a gasket try to put some pressure to the tank,not a bunch, just pressure. Does fuel run into the bucket? What does it look like what does it smell like. Now go under the truck.look for wet spots on any of the rubber hose or metal line. I'm seeing if you're sucking air if so it won't pick up fuel. I'm also trying to stop you from blowing out a line and the hooking things up and sucking a bunch of crap and bad gas into your fuel pump,filter if there is one,and/ your carureator,If your bored you can start hooking up vacuum lines run it on the gas can,don't do all of them at once.So if it quits running right we know it's from whatever line you just hooked up.
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?
 

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