Rear tank bypass

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Aug 18, 2018 | 08:26 AM

Ruckin69

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Rear tank bypass

I had to pull the rear tank for some leaks and on the interim wanted to use the truck. The front tank still has a tank full of gas at the truck does not run. I plugged the fuel selector valve in the back that runs to this facet. The red wire of this facet electric pump is not hooked up so will that solve it or is that stopping flow and why is that even there it the truck has a mechanical fuel pump? I switched the switch on the dash to the auxiliary but the truck is not starting up. Is there another way to bypass that rear tank? What am I missing? Where is the front tank not running correctly? I just bought this truck so I don't know if the front runs or not. Thanks.

Aug 18, 2018 | 09:17 AM

84espy

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1) Remove all hoses from the selector valve and connect front tank hose to hose going to engine.
2) Make sure selector switch is in correct position for the set-up you have now.
I say go with #1 and install 1 new line from tank out to fuel pump.

Aug 18, 2018 | 09:20 AM

Ruckin69

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Good suggestion, do you know why they would have an electronic pump that's not even hooked up on the frame? What am I missing with that? Is that a project that they were going to be doing in the future or was at for something else? Like I said the fuel lines pass through it but it's not even hooked up.

Aug 18, 2018 | 12:08 PM

84espy

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That I don't know, but as long as you have a mechanical fuel pump that is working, then use it. Carbs can only handle so much pressure and you would want to wire a fuel pump so it shuts off in case of your truck being in an accident or roll-over.

Aug 18, 2018 | 12:14 PM

Ruckin69

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Quote:

Originally Posted by 84espy

Did it and worked,(duh, should have thought of that) but I'm just wondering if that selector valve works and still wondering why that electronic pump is on there. When I get the rear tank repaired I'll fool with it.

Aug 18, 2018 | 11:57 PM

mark a.

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Auxiliary is the rear tank, that's why it wouldn't start. FYI from the factory, it takes power to the solenoid to feed from the rear tank, power is off when it's on the front tank.

Aug 19, 2018 | 06:29 AM

Ruckin69

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Thank you...

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Aug 19, 2018 | 09:55 AM

84espy

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Joined: Nov 2009

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Quote:

Originally Posted by Ruckin69

I'm just wondering if that selector valve works.

If you have a battery charger at home, it's real easy to check this out.
1) Mark valve port that goes to engine. Remove selector valve from truck,
2) Make sure that valve has been flushed with water, removing all the gas.
3) Using your mouth, blow through the marked valve port. You will feel air going through one of the other ports.
4) Attach positive charger cable to valve wire and negative to valve body. Make sure the two cables do not contact each other, directly or indirectly like using a metal table. Plug in charger. You should hear a click, since this is a solenoid or switching valve.
5) Using your mouth, blow through the marked valve port. If you feel air going through the port different from step 3, then your selector valve is working.