could I be having a fuel pump problem

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Joined
Feb 20, 2020
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Location
North Georgia
My Car
1972 Mach 1 dark green
Went out to the garage today and found a large pool of fuel under the engine.  My first thought was that I used worm camps on the hoses from the fuel line to the filer, filter to pump.  This was before I found out you should not use worm clamps.  I did not see where the fuel had come from other then there was nothing on top of the engine, intake, etc.  So I replaced the fuel lines mentioned above and the fuel filter with new, non worm clamps.  Started the car, after it was warm I pump the gas to get it out of it's high idle and it died.  Screwing down the idle screw and starting it kept it running but now the idle is high even when I take all the pressure off of the idle screw, even played with mixture screws but idle still high.   I am running a recent Holley 600 cfm while my old Holley 750 is being rebuilt, I should have that back in a few days.  After replacing the lines, clamps and running it there are no leaks as of this typing so I am wondering if, with the gas on the floor and now and idle problem, could there be anything wrong with the fuel pump? 

 
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Yes, your fuel pump could be the source of the fuel leak. Did you check under the car after you replaced the hoses and ran it for a while? Also, see if your oil smells like gasoline. As to the idle and idle mixture adjustment problem I'm guessing you dislodged some debris, or your new fuel lines weren't clean, and some debris got into your carburetor. It appears your fuel pump is still pumping enough to keep the engine running. Your symptoms sound more like plugged passages.

 
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yes, no leaks after running it.

it had been running fine and I had not done anything to fuel lines, carb, etc for quite a while, just happened out of the blue.  Only thing I have been doing is working on the exhaust system. 

Fuel pump looks like an easy bolt off bolt on swap, correct?

 
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 Screwing down the idle screw and starting it kept it running but now the idle is high even when I take all the pressure off of the idle screw, even played with mixture screws but idle still high.  
Your fuel leak is one issue, the idle is another.  Your description is a fairly strong indication of a vacuum leak.   Since you mention you are using a different carb in lieu of one being rebuilt, it could have a crack in the base plate or be warped enough to create vacuum leak.

It might be worth examining.

 
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