Help bringing this K20 back to life..

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Dano500

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So, just bought this K20 and it hadn't run for a couple of years I syphoned out old gas and rotated engine with oil in cylinders and got it to turn on, but it goes straight to high idle, sounding like almost WOT. Noticed that all vacuum lines are gone except brake hose. The left and right vacuum ports on the edelbrock 1405 are capped off. I thought it was the carb because the choke is frozen wide open and I can't get it to move. Throttle arm isn't even touching cam. I am replacing carb, but which vacuum lines are necessary for it to run right?

I know this is very vague, but I don't know what else to ad. I can see that air pump has no belt on it, but the rest of smog is connected except hose that goes to air cleaner as original air cleaner is gone.

Thanks in advance,
-Dan
 

Dano500

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Replaced the frozen carb with a good functioning one. Still not getting any gas to the carb, so I have to start it with the carb. It starts and doesn't high idle anymore, but it turns off within 2-3 seconds.

Even the vacuum canister is gone. Anyone have any experience with which vacuum lines are essential to get it to idle without dying? I can't keep it on long enough to see if the mechanical fuel pump will start working, or if I need to replace it.
 

dvdswan

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Do you have emissions testing where you are at? If not, remove all the emissions crap.

On a vehicle that has sat for a while, I will generally give it a tune-up. Filters (air and fuel), plugs, wires (if they are old), timing, etc.

Vacuum lines, on a non-emissions vehicle IIRC, there was the brake hose to the back of the carb, a side one for vacuum advance on the distributor, and one for the air cleaner. Otherwise, I'm sure there is a vacuum diagram in the service manuals for your year of truck in the library here.
 

Dano500

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Do you have emissions testing where you are at? If not, remove all the emissions crap.

On a vehicle that has sat for a while, I will generally give it a tune-up. Filters (air and fuel), plugs, wires (if they are old), timing, etc.

Vacuum lines, on a non-emissions vehicle IIRC, there was the brake hose to the back of the carb, a side one for vacuum advance on the distributor, and one for the air cleaner. Otherwise, I'm sure there is a vacuum diagram in the service manuals for your year of truck in the library here.
Hello!

I can't get the lines out of manifolds without stripping the nuts, so I guess just cut them all out. Do they just get capped off somehow until I get headers?

I was looking for a way to test/ check if mechanical pump still works as it's only been two years, but I couldn't find anything other than putting fuel in carb long enough to get it to pump fuel from the tank.

Yes, I have the diagram, but I was thinking the only one that would effect it running was the vacuum advance from distributor, but wasn't sure about the rest. According to diagram it tee's off and goes to thermostate and another emissions connection, so I was thinking of just connecting vacuum advance directly to carb only.

Do I have that right?

Thanks,
Dan
 

Ricko1966

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You didn't say year on your k.For now plug every vacuum line on the manifold and carb. It will run that way,then we can start adding things back in 1 at a time.
Don't cut anything out,dont eliminate ANYTHING not until you figure out why it's not running. You don't want to put issues you caused by modifying things,or replacing things into the mix. of why it's not running now. Diagnose then repair,then modify what ever you want 1 piece at a time. Fist thing is you should check compression because nothing you do from this point forward matters if you have 2 cylinders down. Example I changed the,plugs,wires, distributor,the carburetor, the fuel pump, all the vacuum lines and nothing matters it still doesn't run right.Have you run compression? No. Okay found the problem 7 and 5 don't have any compression. Now what? Pull the engine time for a rebuild.
You can eliminate everything from the pump forward by putting a piece of rubber hose on the inlet of the fuel pump pump it in a lawn mower gas can. If it runs the problem is from the tank to the pump.
 
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Ricko1966

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@Dano500 I know you've got a new toy and probably want to start messing with it. But seriously the make it run then work on 1 thing at a time is boring and it won't hurt to do this or that. I've seen this stuff happen so I just want to give you the advice. Say you don't heed the 1 thing at a time idea you change the cap wires and plugs( well that can't affect anything) and you change the fuel pump filter and carb,just because you know they gotta be bad and you went ahead and hooked the brake booster up just cause it's gotta get done. Now when it doesn't run or doesn't run right ,whats wrong? Are the wires on wrong did you break a plug insulator,maybe the brake booster diaghphram is bad,the reman carb you got is defective or do you have a vacuum leak at the base? Changing stuff before you have it running and changing more than one thing at a time,has the potential to make your life suck. I've honestly see this stuff happen.
 

Dano500

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Thanks for the info! I'm going to do exactly that; use the gas can to find out right away. When it was high idling with old carb, it stayed on until I turned it off, but spark and compression sounded fine.
 

Dano500

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@Dano500 I know you've got a new toy and probably want to start messing with it. But seriously the make it run then work on 1 thing at a time is boring and it won't hurt to do this or that. I've seen this stuff happen so I just want to give you the advice. Say you don't heed the 1 thing at a time idea you change the cap wires and plugs( well that can't affect anything) and you change the fuel pump filter and carb,just because you know they gotta be bad and you went ahead and hooked the brake booster up just cause it's gotta get done. Now when it doesn't run or doesn't run right ,whats wrong? Are the wires on wrong did you break a plug insulator,maybe the brake booster diaghphram is bad,the reman carb you got is defective or do you have a vacuum leak at the base? Changing stuff before you have it running and changing more than one thing at a time,has the potential to make your life suck. I've honestly see this stuff happen.
No, I totally agree and I'm going to start with disconnecting from tank and using gas can first. I'll work it from there.

I really appreciate the guidance.
 

Dano500

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I did this will the line to pump. Took this bottle in 10-15 seconds. Is that normal?
@Dano500 I know you've got a new toy and probably want to start messing with it. But seriously the make it run then work on 1 thing at a time is boring and it won't hurt to do this or that. I've seen this stuff happen so I just want to give you the advice. Say you don't heed the 1 thing at a time idea you change the cap wires and plugs( well that can't affect anything) and you change the fuel pump filter and carb,just because you know they gotta be bad and you went ahead and hooked the brake booster up just cause it's gotta get done. Now when it doesn't run or doesn't run right ,whats wrong? Are the wires on wrong did you break a plug insulator,maybe the brake booster diaghphram is bad,the reman carb you got is defective or do you have a vacuum leak at the base? Changing stuff before you have it running and changing more than one thing at a time,has the potential to make your life suck. I've honestly see this stuff happen.
Worked! So at least I know fuel pump is good. Truck took this little container in 10-15 seconds. That normal?
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Dano500

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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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Ricko1966

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Plug all vacuum lines get a bigger jug
 

Ricko1966

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No
 

Ricko1966

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Did you plug all the vacuum lines and get a bigger jug yet
 

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