Author Topic: Fuel System Schematics (and fuel gauge troubleshooting)  (Read 50927 times)

Offline 87r10shorty

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Fuel System Schematics (and fuel gauge troubleshooting)
« on: August 04, 2008, 03:02:31 PM »
Anyone have a fuel line schematic for a dual tank setup on a 87?
Basically what I am trying to do is a dual tank to single tank conversion.
If any one has a write-up on how to do that, that would be great.
« Last Edit: October 22, 2008, 07:29:58 PM by Captkaos »

Offline Captkaos

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Re: Fuel Line Schematic
« Reply #1 on: August 04, 2008, 03:51:32 PM »
If you are eliminating one of the tanks, just pull the switching valve off and connected the lines accordingly.  You will have a supply, return and Vent.  Use EFI rated hose though.

Offline 87r10shorty

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Re: Fuel Line Schematic
« Reply #2 on: August 05, 2008, 08:26:19 PM »
I thought the power for the pumps ran through the switching valve, will the fuel pump still work with no valve in place?
I went ahead and unplugged the switching valve, and ran my lines together bypassing the valve. I tried to start the truck no joy. I don't even hear the fuel pump kick on. What is my next course of action.  While the lines were undone from the valve i went in to the cab turned the key and hit the tank selector switch, gas poured out of the valve, so i would guess the selector valve is good.
« Last Edit: August 05, 2008, 09:34:03 PM by 87r10shorty »

Online VileZambonie

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Re: Fuel Line Schematic
« Reply #3 on: August 05, 2008, 10:14:00 PM »
Click the images to enlarge
« Last Edit: July 19, 2017, 06:09:18 AM by VileZambonie »
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Offline Captkaos

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Re: Fuel System Schematics (and fuel gauge troubleshooting)
« Reply #4 on: May 14, 2012, 11:43:01 AM »














Offline Irish_Alley

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Dual tank wiring schematic
« Reply #5 on: June 23, 2015, 11:15:19 PM »
« Last Edit: February 08, 2017, 09:28:35 AM by Irish_Alley »
If you can’t tell yourself the truth, who can you tell it to?~Irish_Alley

When you have eliminated the impossible, whatever remains, however improbable, must be the truth ~Sherlock Holmes

Online VileZambonie

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Re: Fuel System Schematics (and fuel gauge troubleshooting)
« Reply #6 on: September 23, 2017, 09:25:19 AM »
Dual Tank TBI Gauge

Dual Tank TBI Relay

Single Tank TBI Gauge

Single Tank TBI Relay
« Last Edit: November 06, 2023, 05:05:39 PM by VileZambonie »
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Online VileZambonie

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