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Discussion Starter #1
I seem to be having 3 problems with my car.
1.) I'm only getting at best 11mpg with a 250 inline 6. It more around 9. That could be a number of problems.

2.) I have heard from a few guys that the mixture of gas is to rich. What does that mean, and how can i change that? The tail pipe likes to give out black smoke when i start it up, and the tailpipe is also caked with black stuff. What can i do about it?

3.) Recently at a car cruise I drove my car down main street for about 1 mile, turned around and about 3/4 a mile left, I was smoking like crazy. It was about 5mph the entire time, alot of stopping and starting. on my way home, i noticed a real bad tapping from the engine, which turned out to be lack of oil. When i check the oil, I had burned about 1 quart of oil. and was nearly empty. What Could have cause all of the oil to burn, and was that the cause of the smoking? Im at a complete loss, and am not sure what i can do.


Any input on these problems would be greatly appriciated, and are they in any way related to my carburator? If so Please get back to me with some advice, if not, thanks anyways.
 

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Welcome to the site! I'm in the South Hills :) What type of carb are you running? What is your initial & total timing set to?
 

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Discussion Starter #3
DriveWFO said:
Welcome to the site! I'm in the South Hills :) What type of carb are you running? What is your initial & total timing set to?
its a Single-Barrell Carb that was on the car - 1975,4Door,250ci,1-bbl...


Your guess at the initial and total timing is as good as mine. How would I check it, and what should it be?
 

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go to your local Harbor Freight store and buy the cheap $29 timing light with the dial advance on it. read the directions on how to use the timing light, or look it up on the web.

your initial timing is the timing is the timing when your engine is idleing and the vacuum advance hose (the only hose going to your distributor) is diconnected and plugged. normally around 12 degrees BTDC or so.

Now re-attach the vacuum hose to your distributor and have someone slowly push on the accelerator of your car until the timing moves to its farthest position. This is your total timing (usually like 36 degrees BTDC or so for a SB chevy V8)

There is a lot of info on the web, just google "check my timing"
 

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Check your oil every time you fill with gas. It is not that noticable to use a quart in 500 miles on a worn motor. Check the fuel system for leaks. A one barrel carb should not deliver that much fuel. Look for stains around the gas tank. A good fitting gas cap. Then follow the fuel line to the carb. Gas evaporates fast. It can leak with out leaving a puddle. Earl
 

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With the problem you mention it could be your carb. The needle valve that controls the gas level could be allowing excessive fuel to flow flooding the motor. It could be many things. It could be a dirty air filter. Has the engine been tuned up and have you done a compression test to know the engine is in decent shape internally?
 

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If you'd like to stop by for a minute this weekend, my father and I are in Cranberry. We can help you with your car if you help throw some plywood on the roof lol.

Kev
 

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Discussion Starter #9
I have not done any sort of tune-up yet. I have only checked the timing, and also found the air to fuel ratio was somewhere around 18.5 Now I am not sure what the 18.5 stands for, but we lowered it to just below 18. The fuel seemd to be to rich, so Was turning it down the correct thing? Is 18 Good or should it be lower? or higher?

I am trying to sift through any minor problems first, before I get new plugs and wires.

All the suggenstions yins have is great, please, keep it comming.
 

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Not sure how you arrived at the fuel ratio of 18 to 1 so I'll just leave that alone. With your seemingly limited experience you might be well served to take Novaboy099 up on his offer to help. There are so many possibilities that a guy with car experience and having his hands right on the car it would be well worth the trip IMHO. RM
 

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Real McCoy said:
Not sure how you arrived at the fuel ratio of 18 to 1 so I'll just leave that alone. With your seemingly limited experience you might be well served to take Novaboy099 up on his offer to help. There are so many possibilities that a guy with car experience and having his hands right on the car it would be well worth the trip IMHO. RM
When I hooked the vacume gauge up to the carburator, it read 18. We did that change how much air was mixing with the fuel. i know for a fact its not 18:1. I have a idea that its under control. and if i had the time, i would definalty check it out, but i dont see that happening to soon. Time is short, and so is cash. It gets me to A to B, and Back to A, I just was looking for some good advice on how to go further, longer. But thanks for your consideration
 
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