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Discussion Starter · #1 ·
so.. I've got a 64 with the 194 inline six. I understand its not a real big mover, but its what i got :devil:

I rebuilt the carb when i first got the car, and have been messing with it ever since. Its a rochester single barrel, but its from a 76 (i believe) and is definitely not the stock one, tho it is still a Rochester monojet. I've plugged off the extra vacuum ports, so all there is now is advance for the distributor and transmission kickdown (i think thats what it is anyhow..)

It runs good now at high rpms, like when i'm driving on the freeway, but starts hard when its cold and doesn't idle very smooth. the timing is right on, point gap is close (i dont have a dwell meter, just gapped them)

When i'm taking off from a stop, it doesn't have any low end power. I havn't drivin one of these when runnnig good, so i dont know what i'm comparing it to, but its ridiculously slow off the line. Could it be running lean? will this engine be making enough vacuum that it pulls plenty of fuel at high rpm even if its lean at idle? If anyone has any ideas on this i'd love to find out what to do..
 

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Discussion Starter · #2 ·
forgot to put in there--
I've been thinking also of swapping to a 2 barrel. I dont have the money to buy a new one, so was trying to find out what cars may have came stock with one. I can run to pick and pull then rebuild it for a reasonable amount, I just dont know what cars to look for.

Thanks!
 

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Don't assume the problem is with the carburator until you diagnose why it's running poorly. When diagnosing it's sometimes good to verify and eliminate, what it isn't and in the process you will eventually find out what ithe problem is. You don't want to guess or speculate. Every component has a test that will prove if it is working properly. This may require buying or borrowing tools.

First thing you want to verify is the pumping condition of the engine.
A compression gauge is needed for this.
There are several methods that give different results.
1. Crank to the highest value. This will give you your max pumping pressure. It useful for octane calcs but not for engine condition.
2. 4 puffs method. This is the method you use for checking sealing condition between cylinders.
3. Running compression. Not for novices so I won't discuss this one.

Next is the vacuum gauge. This gauge will tell you alot. There are sites and books that show what the needle values and movements indicate. Every tuner out to have one. They are cheap and very useful.

Timing light. Mandatory. Nobody should be tuning without one.
Tach or Multimeter with rpm function.
Mity vac for testing vacuum cans or pulloffs.

Shop manual. It's surprising how many people have a car for years and don't have basic specs. Don't rely on the Internet.
 

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A few things to check.

1. Choke not closing when cold would cause hard start and poor running until it warms a little.

2. Accelerator pump not working will make it fall on its face when first starting out.

3. Are all the intake bolts tight, no vacuum leaks on the intake gaskets.

4. Compression check on the cylinders. Make sure the miss isn't mechanical.

5. When dark start car and open the hood, no lights. If you see sparks from the plug wires, time to replace them. Also inspect the plug wires for burned/worn ends etc.

6. Does the idle adjust screw work well on the carb? You may have it just a little too lean or rich.
 

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Discussion Starter · #5 ·
Thank you both for the tips on this. I've checked the choke, and its closed tight when cold (before you accelerate) and wide open once the engine warms up. also, the accelerator pump is working correct. I have a vacuum gauge, though i'm still learning what all the movements mean with it. I have a book about it.. its amazing what you can learn. also +1 with the shop manual Paul, thats a very important thing to have, i found mine at Powels books for 6 bucks.. :D

I'll keep messing with it, and i'll have to get the compression tester. I think my friend has one, i'll give him a call. I've replaced wires, plugs, cap, rotor and points, but i'll check the manifold bolts also.

thanks again! these cars are a great knowledge builder, I've done lots of part swapping, but troubleshooting is where you learn to be a real mechanic.. well, something like that anyhow. :eek:
 

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Check the carb gasket, if the carb came off a 76' there is the potential that it also came with emissions and if you look at the bottom of the carb there may be heat marks. These marks will cause the metal of the carb to bend a little causing a poor seat.
I have a bronco that had emissions and when I took off the emissions plate I couldnt get it to run well at all unless I was in the high rpm. It turned out to be the carb seal due to heat stress from the emission plate,
Take your carb off and do a blue check on a flat surface to make sure its flat.
If you dont know how to do this, get some blue die and smear it on a known flat surface, a piece of steel or something, and set the carb down on it. Then lift it up straight and look at the blue die marks that will transfer to the bottom of the carb, it should have blue mark all the way around, mine was only touching on the bolt holes. This caused a weak seal on the gasket and I was sucking air and didnt know it.
 
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