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Old 02-26-2014, 09:16 PM   #1
ozkiwi
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New fuel pump removes carb flat spot ???

My quadrajet is really worn so it got the blame for my truck not being able to handle flooring the throttle I have always had to feed it in progressively ever since I fitted my new crate motor it has had with a big flat spot and hessitation.
So when I replaced the fuel pump recently I was suprised to find it completely gone.It is much more responsive as well even with my shot Quad.


Finally a win with this old girl.
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Old 02-26-2014, 09:22 PM   #2
SkinnyG
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Re: New fuel pump removes carb flat spot ???

That kinda makes sense. The Q-jet doesn't have a very large float bowl, so if the engine draws fuel faster than the pump volume can refill it, you'd get a flat spot. Makes sense!

I just got through doctoring my worn out Q-Jet using Cliff Ruggles book. I also put in new throttle shaft bushings, too. Runs really swell now!
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Old 02-26-2014, 10:31 PM   #3
ozkiwi
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Re: New fuel pump removes carb flat spot ???

Quote:
Originally Posted by SkinnyG View Post
That kinda makes sense. The Q-jet doesn't have a very large float bowl, so if the engine draws fuel faster than the pump volume can refill it, you'd get a flat spot. Makes sense!

I just got through doctoring my worn out Q-Jet using Cliff Ruggles book. I also put in new throttle shaft bushings, too. Runs really swell now!
See my latest post I think you may be able to enlighten me.
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Old 02-27-2014, 06:12 AM   #4
donut
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Re: New fuel pump removes carb flat spot ???

Cool, mine's currently waiting for a fuel pump. Put-puts fine around town, but hit the throttle and it'll cut out.

Surprise! Sometimes things just work out.
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Old 02-27-2014, 08:44 PM   #5
willett
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Re: New fuel pump removes carb flat spot ???

Hmmmmm..... I oughta give that a try
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Old 02-28-2014, 10:23 AM   #6
520CheyenneK10
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Re: New fuel pump removes carb flat spot ???

Well I just put a new Fuel Pump on my 73' K10 and now I "Have" flat spots under acceleration especially on hills so wtf ?? I also did a full tune up at the same time and think maybe i needed to set the SP gap at .045 instead of the .035 the data plate says since I have a converted HEI. Gonna re-gap and different (HEI) rated plug wires this weekend. Gotta love these old gals...I'll post my findings after the changes are made.
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