Author Topic: additional fuel filter  (Read 1418 times)

Offline bedwards

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additional fuel filter
« on: May 13, 2020, 08:09:22 AM »
Is there a good place to put an additional fuel filter on a bone stock 85 305 with dual tanks?

thanks

Offline zieg85

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Re: additional fuel filter
« Reply #1 on: May 13, 2020, 08:54:33 AM »
While not convenient I've extended the rubber line before the mechanical fuel pump as to not cut any steel lines.  That way you can change it back stock when whatever issue you are having with your fuel supply is resolved.
Carl 
1985 C20 Scottsdale 7.4L 4 speed 3.21
1986 C10 under construction
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Offline bedwards

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Re: additional fuel filter
« Reply #2 on: May 13, 2020, 09:17:31 AM »
So you just put an inline filter before the fuel pump? Thats a 3/8 line isn't it?

Offline bd

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Re: additional fuel filter
« Reply #3 on: May 13, 2020, 09:34:07 AM »
Permanently installed fuel filters should be located on the pressure or outlet side of the fuel pump.  Only coarse sieve filters (~100 microns) should be used on the suction side.
Rich
It's difficult to know just how much you don't know until you know it.
In other words... if people learn by making mistakes, by now I should know just about everything!!!
87 R10 Silverado Fleetside 355 MPFI 700R4 3.42 Locker (aka Rusty, aka Mater)

Offline bedwards

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Re: additional fuel filter
« Reply #4 on: May 13, 2020, 10:12:44 AM »
What kind is that? Sorry for the dumb question.

Offline bd

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Re: additional fuel filter
« Reply #5 on: May 13, 2020, 10:36:47 AM »
Think of it as a screen that keeps trees and little people from being pulled into the fuel pump.   :)

Fuel pumps are designed to push fuel.  Although mechanical fuel pumps develop considerable draw, they can be damaged in the long term if forced to draw excessive vacuum such as might occur if a pre-filter restricts.
Rich
It's difficult to know just how much you don't know until you know it.
In other words... if people learn by making mistakes, by now I should know just about everything!!!
87 R10 Silverado Fleetside 355 MPFI 700R4 3.42 Locker (aka Rusty, aka Mater)

Offline zieg85

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Re: additional fuel filter
« Reply #6 on: May 13, 2020, 10:44:55 AM »
Think of it as a screen that keeps trees and little people from being pulled into the fuel pump.   :)

Fuel pumps are designed to push fuel.  Although mechanical fuel pumps develop considerable draw, they can be damaged in the long term if forced to draw excessive vacuum such as might occur if a pre-filter restricts.

All though I eluded to it, mine was a temporary situation.  I bought a truck that had been sitting for a while and I did this to keep the truck running before I could get a new tank installed as it was rusty inside.
Carl 
1985 C20 Scottsdale 7.4L 4 speed 3.21
1986 C10 under construction
https://www.facebook.com/groups/248658382003506/