6 port selector valve help

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K5BEAST

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installing an auxiliary tank in my rock crawler. so i bought a 6 port fuel selector valve. after hooking it up the aux side works as it should. when i switch it back to the main tank, it runs out of fuel and dies. I can disconnect it all and go back to just the original system set up and the truck runs fine so i know its not the fuel pump. sometimes when i have the valve hooked up to the main tank, it will run but fall on its face when i accelerate the engine. Like its not getting enough fuel.

ive verified correct voltage at valve, polarity is switching because i can hear the pumps swap over. it seems like the valve just isnt opening up all the way. feeling very frustrated. ive had the valve in and out 3 times now. it seems to bench test fine by blowing air through it and actuating the valve to see if it stops flow and switches ports.

am i missing something here? any help diagnosing this would be great!!
 

Ricko1966

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In line 7 you say pump,in line 12 you say pumps. Do you have two pumps or 1 pump?
 

K5BEAST

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Got it solved.

To answer your question though, I have two pumps, one for each tank. One is the original stock one in stock tank. Second is inline between aux tank and switching valve.

Problem ended up being a misprint in the included instructions for the valve. It power to the pump is teed off of the power line between dash switch and valve. Since it operates by switching polarity to accuate the valve, power gets sent to each pump respectively. The issue was per must go to the corresponding pump depending on which way the valve is switched to. The instructions had these connections backwards. I switched the power to the pumps around and it all works great now.

The connections in red in the pic were backwards.

Hopefully this can help someone in the future.
 

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SquareRoot

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Got it solved.

To answer your question though, I have two pumps, one for each tank. One is the original stock one in stock tank. Second is inline between aux tank and switching valve.

Problem ended up being a misprint in the included instructions for the valve. It power to the pump is teed off of the power line between dash switch and valve. Since it operates by switching polarity to accuate the valve, power gets sent to each pump respectively. The issue was per must go to the corresponding pump depending on which way the valve is switched to. The instructions had these connections backwards. I switched the power to the pumps around and it all works great now.

The connections in red in the pic were backwards.

Hopefully this can help someone in the future.
Thanks for following up and posting the problem and how you resolved it.
 

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