[Tyrod]

I have an 87 short box w/ the dual gas tanks and the switch on the dashboard, except the previous owner removed the driver side tank. As of the last couple of months I have been having a problem w/ it starting every now and then, when this happens I can usually flip the switch a few times and it will fire no problem, however this weekend it wouldn't start at all so I am thinking of bypassing the switch. It will run when I dump fuel in the throttle body but that is the extent of it. Anyone else have this problem or any suggestions. It is a four wire switch. Thanks in advance.

 

[KWTMECH]

If the tank has been removed then crawl underneath and bypass the valve with the fuel lines altogether----problem solved

 

[Tyrod]

I will do that, would I still need to bypass the switch or just leave it be? I would think the switch would control which pump to activate and would still need to be dealt with?

 

[KWTMECH]

AH, forgot about the TBI. The drivers side tank is the primary tank. So when the ignition is shut off, the spring in the switching valve diverts back to the primary/drivers tank. When power is put to the switch it swaps to the passenger side. You will have to find out which wires at the switching valve control not only the fuel pump but also the sending unit for your gauge and make a jumper wire or just do a cut and splice.




Edit: don't forget to not only jump the fuel line but the return also


Edit again: valve has letters on it, or the connector
A-right sender
B-to fuel gauge
C-left sender
D-left fuel pump (tan)
E-right fuel pump (gray)


according to the diagram the pump switches at the switch (in dash) and the sender switches at the solenoid (frame)

 

[Tyrod]

Thanks alot for the help, this can get frustrating! From what I understand now is if I splice terminals C & D which are for the left side pump and sender, as well as bypass the valve on the chassis I should be good to go correct. Thanks again

edit: could you possibly send a copy of the diagram

 

[KWTMECH]

Cannot send the diagram from this computor. Have to do it when I get home. C & D will be wrong. A and B for the sender

 

[Tyrod]

That would be great, thanks

 

[KWTMECH]

try this

 

[Tyrod]

Thanks alot, I got it up and running last night but never did get the gauge wiring tracked down so this will help a ton. I ended up bypassing the diverter valve and finding the hot lead out of the fuse box and connected that to the grey wire for the pump and it fired right up. Thanks again