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Mechanical fuel pump replacement question.

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Old May 11, 2017 | 08:05 PM
  #1  
siuol's Avatar
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From: Connecticut
Car: 1987 Firebird Formula
Engine: Carbureted - 305
Transmission: 700R4
Mechanical fuel pump replacement question.

Hi, I am going to replace the original mechanical fuel pump on a 305 carburetor engine.

There are two fuel lines going to the pump from the tank, one larger, I assume its the fuel supply and a smaller one, which might be the return line. My question is: if I remove the rubber lines to replace them, will I get fuel flow from the tank. Is the tank higher or lower than these lines?

thanks in advance,

Louis
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Old May 11, 2017 | 08:08 PM
  #2  
redneckjoe's Avatar
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From: Spring Hill, Fl.
Car: 87 iroc-z
Engine: 454
Transmission: th350
Axle/Gears: 3.73
Re: Mechanical fuel pump replacement question.

you shouldnt get any flow.
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Old May 11, 2017 | 09:02 PM
  #3  
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Re: Mechanical fuel pump replacement question.

Take the gas cap off first.
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Old May 11, 2017 | 09:18 PM
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From: Meriden, CT 06451
Car: 84 TA orig. 305 LG4 "H" E4ME
Engine: 334 SBC - stroked 305 M4ME Q-Jet
Transmission: upgraded 700R4 3200 stall
Axle/Gears: 10bolt 4.10 Posi w Lakewood TA Bars
Re: Mechanical fuel pump replacement question.

Buy the Carter M6626 pump. Only about $20. It will be an upgrade.
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Old May 12, 2017 | 01:13 AM
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Car: 1984 Camaro Berlinetta
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Re: Mechanical fuel pump replacement question.

Don't buy a cheap Chinese fuel pump,...... Most cheap aftermarket pumps have a weak internal spring on the 'rod lever' that causes a "click" or "TICK" sound that sounds like an internal engine problem. When sitting in the car the sound seems to come from the tranny tunnel like a cracked flywheel or a bad rocker arm / lifter tick.

This pump had only a few hundred miles on it when it started Ticking. The TICK was worse at start-up but was always present. I thought the newly rebuilt engine had a major problem - but it was just a cheap pump. ( worked fine ) Re-set the rockers 3 times and then replaced the rollers with stock steel and even had the car on ramps ready to pull the tranny cause I figured it had to be a cracked flywheel. I got under the car on ramps after starting it up and realized that I could hear the TICK loud near the back driver tire ??? That's when I realized the TICK sound was traveling thru the fuel line............





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Old May 12, 2017 | 07:53 AM
  #6  
siuol's Avatar
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From: Connecticut
Car: 1987 Firebird Formula
Engine: Carbureted - 305
Transmission: 700R4
Re: Mechanical fuel pump replacement question.

Thanks guys, I have the carter pump on order.I am glad to see we are on the same boat on pumps.

Louis
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Old May 12, 2017 | 10:29 AM
  #7  
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From: Littleton, CO USA
Car: 82 Berlinetta/57 Bel Air
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Axle/Gears: 12B-3.73/9"-3.89
Re: Mechanical fuel pump replacement question.

Originally Posted by John in RI
Don't buy a cheap Chinese fuel pump,...... Most cheap aftermarket pumps have a weak internal spring on the 'rod lever' that causes a "click" or "TICK" sound that sounds like an internal engine problem. When sitting in the car the sound seems to come from the tranny tunnel like a cracked flywheel or a bad rocker arm / lifter tick.

This pump had only a few hundred miles on it when it started Ticking. The TICK was worse at start-up but was always present. I thought the newly rebuilt engine had a major problem - but it was just a cheap pump. ( worked fine ) Re-set the rockers 3 times and then replaced the rollers with stock steel and even had the car on ramps ready to pull the tranny cause I figured it had to be a cracked flywheel. I got under the car on ramps after starting it up and realized that I could hear the TICK loud near the back driver tire ??? That's when I realized the TICK sound was traveling thru the fuel line............





Had that same problem with a newly rebuilt engine with brand new fuel pump in the 80's (not in a 3rd gen, though). Sounded like a diesel.

on the 6626.
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