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Fuel Filter b4 Electric Pump or After?

  • Thread starter Thread starter palerider94
  • Start date Start date May 3, 2010
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palerider94

Member
Feb 21, 2006
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May 3, 2010
#1
  • May 3, 2010
  • #1
Mounted electric pump on my car. Made sure it was close and below gas tank. Question I have since these pumps are made to push fuel instead of pull - should I have mounted the filter after the pump instead of before or does it make that much of a difference - just curious on what others have done.
 

Rusty67

20+ Year Stangneter
Dec 3, 2002
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#2
  • May 4, 2010
  • #2
With an electric pump it is a MUST to have a filter BEFORE the pump. Doesn't hurt to have one up front near the carb as well, who knows what kind of crap is running around in your gas lines between the pump and the carb.

When I put one on my friends Cougar we put one pre-pump and just before the carb as well. Fuel filters are cheap, pumps and carbs are expensive.
 

tx65coupe

Active Member
Nov 29, 1999
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May 4, 2010
#3
  • May 4, 2010
  • #3
I would put the filter after the pump. Thats how most cars come factory.
 

Rusty67

20+ Year Stangneter
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#4
  • May 4, 2010
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The reason the filter is after the pump in modern production cars is because they use an in tank pump that has a fuel tank which is known to not have rust and other sediment from 40+ years of service which can clog/ruin a fuel pump.

In tank electric pumps are the way to go if you can swing it. They are quieter and more reliable.
 

tx65coupe

Active Member
Nov 29, 1999
1,551
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May 4, 2010
#5
  • May 4, 2010
  • #5
Although I run a mechanical pump, I have 2 filters one before the pump and one before the carb. Like he said, pumps and carbs are expensive, filters are not.
 
D

D.Hearne

New Member
Sep 29, 2000
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south louisiana
May 4, 2010
#6
  • May 4, 2010
  • #6
Rusty67 said:
With an electric pump it is a MUST to have a filter BEFORE the pump. Doesn't hurt to have one up front near the carb as well, who knows what kind of crap is running around in your gas lines between the pump and the carb.

When I put one on my friends Cougar we put one pre-pump and just before the carb as well. Fuel filters are cheap, pumps and carbs are expensive.
Click to expand...

Ditto, this is what I do as well. And I never have carb problems.
 

PM 65

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Nov 2, 2005
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Austria (Europe)
May 4, 2010
#7
  • May 4, 2010
  • #7
D.Hearne said:
Ditto, this is what I do as well. And I never have carb problems.
Click to expand...

This is also my setup, one filter before and one after the pump (mechanical). No dirt in the carburetor since then...
 
P

palerider94

Member
Feb 21, 2006
573
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19
May 4, 2010
#8
  • May 4, 2010
  • #8
I got mine mounted before the electic pump. That seemed to make sense to me. Did not want to get trash in it. Reason I questioned is that someone looking at my set up mentioned it would restrict pump making it work harder.
 

PM 65

Active Member
Nov 2, 2005
72
0
26
Austria (Europe)
May 4, 2010
#9
  • May 4, 2010
  • #9
palerider94 said:
I got mine mounted before the electic pump. That seemed to make sense to me. Did not want to get trash in it. Reason I questioned is that someone looking at my set up mentioned it would restrict pump making it work harder.
Click to expand...

As long your filter is not undersized, i see no problem with that. These things are aviable in all possibly dimensions with big filter inlets. I always used 1 step higher as needed and never had any problems on any car. Other suggestions?
 
D

D.Hearne

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Sep 29, 2000
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May 4, 2010
#10
  • May 4, 2010
  • #10
palerider94 said:
I got mine mounted before the electic pump. That seemed to make sense to me. Did not want to get trash in it. Reason I questioned is that someone looking at my set up mentioned it would restrict pump making it work harder.
Click to expand...

I'm running a 35 gal/hr Mr.Gasket pump. It supplys plenty of fuel for full power runs (331 topped with 3 - 2 bbl carbs)until the inline filter between it and the tank gets full of trash. That's when I know the filter needs changing..........the engine starves for fuel.
 

blown65

Founding Member
Jul 7, 1999
1,938
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39
Queen Creek Arizona
May 4, 2010
#11
  • May 4, 2010
  • #11
Mines on after the pump, but I have an aluminum fuel cell and use gas out of cans so its pretty controlled what gets pumped.

Stock tank, I would always have one prior to the pump.
 

iskwezm

10 Year Member
May 24, 2005
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Rowland Heights,California
May 4, 2010
#12
  • May 4, 2010
  • #12
some pumps will cavitate with a pre filter
 

Rusty67

20+ Year Stangneter
Dec 3, 2002
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109
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May 4, 2010
#13
  • May 4, 2010
  • #13
I would think that if a pump is having problems with cavitation because of the filter it is provably because the filter isn't big enough to supply the pump what it needs in all conditions.
 
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