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Discussion Starter · #1 ·
Well, after hooking up a charger onto the battery for a little while, I got the car to turn over. The only way I could get it to start was by holding down the gas pedal. And, while it was running, it was running really rough. It was chugging really unevenly, and shaking a lot. My thoughts on the problems are the following:

Bad gas. But I have a fuel line right now running directly from a gas can full of new gas to the fuel pump, and the old line between the fuel pump and the carb.

Maybe the old line is clogged. There is a small amount of gas running through the filter, it only stays about halfway full. I'll get a new line in a little bit, but want to make sure I cover ever possibility of the problem, so I'm not going to stop with that.

A bad fuel pump. However, the pump is new, we put it in as soon as we got the car.

Badly tuned carb? It is weird that the car only runs when I'm holding the pedal to the floor. As soon as I lift it up, it dies. Does that sound like a carb problem?

Bad timing. But we know that the PO had the timing fixed at the same time he had the car get a tune up, as well as having the compression checked (they came out fine)

So, those are my guesses. Any idea on how I can check? Just go adjust the mixture/idle screws on the carb till it runs better, and add in a new fuel line? Will that probably (hopefully) be the culprit?
 

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Don't rule out the ignition system either. if its been sitting for a while, chances are that the points need some work.

I would venture to guess that the carb needs to be rebuilt, or at least taken apart and throughly cleaned. you also may have a vacume leak somewhere (check power brake booster and the vacume line for the transmission, if its an automatic). there may be something wrong with your choke setup too.

I remember you mentioned that someone had done a compression test and one of the cylinders was low. if it is 20 or so lbs lower than the others its probably not any part of your problem, but if one of the cylinders was close to or at zero pounds of compression for whatever reason (burnt valve, wiped cam lobe, badly scratched cylinder wall, etc) the engine will not run well at all.

also, check the firing order to insure that it is correct for that engine. remember, non HO 302's use a different firing order than the HO's and 351's, which both use a different firing order than a sbc.

- Jason
 

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Discussion Starter · #3 ·
I'll check out the ignition problem, thanks for the tip.

I'll also look into a carb rebuild kit, and the choke set up.

No power brakes, but I'll check out the transmission vacuum line.

I don't remember the exact numbers for the compression, but I remember that they were close enough to be in the safe zone. One was like 12 lower than the others, which were within 2 or 3 of each other. I'll look into that if nothing else works.

It's not a V8. It's a '74 250 I6. I don't think that makes a difference, but just so you know. I'll still check the firing order.

Thanks for your help, hopefully by the time my parents get back from their cruise Friday morning, it'll be up and running. Cross your fingers.
 

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Firing order for that engine is 1-5-3-6-2-4 and the rotation is clockwise.

-- Suggest you not take the PO's word for anything. He supposedly had it recently tuned up, but bottom line, it will hardly run.

-- Check the timing with a light.

-- Pull the plugs and see what they look like. The ones not firing will appear oil soaked, but this is probably just unburned gas. Plug gap is 0.035".

-- Check the points gap. Should be 0.025".

-- Check for spark at each cylinder while it's running (be careful, those shocks hurt! Use heavily insulated pliers) Isolate the cylinders that aren't firing. When the culprits are found, see if there is spark to the plug, or if the plug is bad from setting around.

-- Check the wires where they plug into the distributor cap. Make sure they are shoved in there good.

-- Inspect the distributor cap and rotor. Look closely for cracks. If they don't look absolutely new, replace them (along with the points and condensor).

-- Turn the air/fuel mixture screw all the way in to where it just bottoms out (do not force), while counting the turns. Then, turn it back out 2 1/2 turns.

Get back to us with the results after doing the above. Have Fun!
 

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Make sure the choke is open. If it is, I'd bet on a stuck needle valve or sunken float.
 

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Discussion Starter · #6 ·
Alright, So now the car is starting, and dying immediately. Let me tell you what I did, it might let you know what was wrong in the first place.

The plug wires are all in the correct order, but I have one question about the distributor. I was expecting the #1 position on the distributor cap to be at the farthest point away from the front of the car, but it was at the front/driver's side. I thought maybe it was 180* wrong, and that's why the car was running so bad, so I flipped it around, and the car wouldn't start. So I put it back.

The distributor looked new, inside and out. I made sure all the wires were plugged in well.

I can't get the spark plugs out. I've never done it before, so maybe I'm doing it wrong. I'm trying to screw them out. It's hard to get a good grip though. Can somebody please explain the process to me, so I know what I'm doing wrong.

I tried adjusting the mixture screw, but now the car won't start. I twisted the mixture screw all the way in, then out 2 1/2 turns. When I tried starting the car, as soon as I let go of the key, it dies. I tried letting the screw out some more, back to where it was, but it doesn't help. I also tried messing with the idle screw, to no avail.

About the choke. I noticed that the butterfly was closed last night, so I tried holding it open with the car running. The car ran a heck of a lot better, but still died after letting off the gas pedal. I tried holding it open again today, and after one try, it stayed partially open (it was alwyas fully closed the other times). I thought this was a good sign, like maybe something got diconnnected, but then fixed, and I tried starting the car, but no go. And now it's back shut all the way.

How do I find and fix it if it is a stuck needle valve or sunken float? Thanks for the help, I hope we dcan get it running soon.
 

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Go to your local auto parts store and get:

1. feeler gauge

2. spark plug gap tool w/gauge

3. spark plug sockets

All of this will cost under $10, but not optional. You need this to do anything to the car. You also need a timing light, so beg, buy, borrow, or steal one.

One question, does the carburetor flood when you are trying to start it? This would be where you will see gss on the outside of the carb, and maybe even a puddle at the base of it. This indicates a sticking or stuck float, or other internal problem. Also:

IMPORTANT: When you are trying to start it, have a fire extinguisher handy to put out any fires that may result from a backfire. This may keep you from burning up the car, and the house too if sitting in the garage.

When you get the feeler gauge, check the points setting first. The points must be sitting with the rubbing block on the high point of the cam. Make sure they are set right.

Take the air cleaner off and stick a screwdriver down the throat to hold the choke plate open. Do NOT have somebody do this by hand while they are looking down the carb. If it backfires, they will be looking for false eyebrows to wear!

You may still have something stuck inside the carb, but need to troubleshoot all items listed in my previous post before I would recommend tearing into it. Good Luck!
 
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