Dual Tank Switch Dilema

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Raybob9289

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I'm sure this question has been answere a zillion times on here somewhere.
So I made the jump to the Pollack modern dual tank valve. Do I really have to but a toggle switch for the dash?? There's gotta be a way to wire the stock 1977 dash switch?
Any help I'll send you a six pack....
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Snoots

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It's just a simple DPDT (Double Pole-Double Throw) switch. Should be an easy swap. The 2 pins in the center are your mains.
 

Raybob9289

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It's just a simple DPDT (Double Pole-Double Throw) switch. Should be an easy swap. The 2 pins in the center are your mains.
Thanks for your help, but I'm just a Frame Carpenter. Wiring hurts my brain.
are you talkin about the original GM dash switch???
 

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Yes.
DPDT On-On
Functions like two spearate SPDT switches operated by the same actuator. Only two loads can be On at a time.
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SirRobyn0

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I'm sure this question has been answere a zillion times on here somewhere.
So I made the jump to the Pollack modern dual tank valve. Do I really have to but a toggle switch for the dash?? There's gotta be a way to wire the stock 1977 dash switch?
Any help I'll send you a six pack....
You must be registered for see images attach
We have done this at the shop more than once. The problem is I won't be back to the shop until Monday and my notes are there. If you don't get an answer your happy with by Monday morning tag me and remind me and I will see if I can find my notes and post them.
 

Raybob9289

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Yes.
DPDT On-On
Functions like two spearate SPDT switches operated by the same actuator. Only two loads can be On at a time.
You must be registered for see images attach
Thanks Dude,,
 

Raybob9289

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We have done this at the shop more than once. The problem is I won't be back to the shop until Monday and my notes are there. If you don't get an answer your happy with by Monday morning tag me and remind me and I will see if I can find my notes and post them.
That would be Awesome..
 

fiatplus

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I recently went thru this same conversion issue on my 1975. Your drawings look very familiar.

After more hours than I would like to admit, I was unable to get the fuel gauge to work off the later dual pole toggle switch, so now I have two switches. The new toggle for the tanks, the old original rocker for the gauges. On my truck the right tank is the primary (changed on later trucks), and that gauge works. But the left, no matter what, refuses to work. I suspect the brown wire in the back at the tank solenoid has a bad connection somewhere before it turns into blue at the rocker switch upper left terminal.
I even ran a new wire from the sending unit to the rocker switch, but that didn't work. And a new ground tank to battery. didn't help either.

I am currently driving around on the left tank and when it sputters I will switch to the tank to the right.
 

SirRobyn0

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Ok according to my notes you will either need to use the switch that came with the kit or order a later production OEM type (80s) switch.

Either way to not end up in the position that flatplus is in you will need to wire the gauge wire down to the switch valve on the frame, because the new style valve handles the gauge change now, where as in the old set up the switch on the dash did.

The problem is that the current switch is only capable of sending power, or shutting off power to the valve and you need a switch that is capable of sending both power and ground to the valve and reversing the polarity. The later production OEM switches could do that, and from looking at my notes it looks like we have either purchased a later switch and wired it to that, or we have left the stock one on the dash to fill the hole and used the switch from the kit and simply installed it where the customer wanted. Either way you do need to run the wire from gauge to the valve now.

So the one line answer is yes we have done this at the shop but we have ordered and installed a later production factory style switch or used the kit switch.

Probably not the answer you were hoping for. but hopefully helpful.
 

Lowered87

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I recently went thru this same conversion issue on my 1975. Your drawings look very familiar.

After more hours than I would like to admit, I was unable to get the fuel gauge to work off the later dual pole toggle switch, so now I have two switches. The new toggle for the tanks, the old original rocker for the gauges. On my truck the right tank is the primary (changed on later trucks), and that gauge works. But the left, no matter what, refuses to work. I suspect the brown wire in the back at the tank solenoid has a bad connection somewhere before it turns into blue at the rocker switch upper left terminal.
I even ran a new wire from the sending unit to the rocker switch, but that didn't work. And a new ground tank to battery. didn't help either.

I am currently driving around on the left tank and when it sputters I will switch to the tank to the right.
Look for broken wire, bad connection plug or bad sending unit.
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Raybob9289

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Ok according to my notes you will either need to use the switch that came with the kit or order a later production OEM type (80s) switch.

Either way to not end up in the position that flatplus is in you will need to wire the gauge wire down to the switch valve on the frame, because the new style valve handles the gauge change now, where as in the old set up the switch on the dash did.

The problem is that the current switch is only capable of sending power, or shutting off power to the valve and you need a switch that is capable of sending both power and ground to the valve and reversing the polarity. The later production OEM switches could do that, and from looking at my notes it looks like we have either purchased a later switch and wired it to that, or we have left the stock one on the dash to fill the hole and used the switch from the kit and simply installed it where the customer wanted. Either way you do need to run the wire from gauge to the valve now.

So the one line answer is yes we have done this at the shop but we have ordered and installed a later production factory style switch or used the kit switch.

Probably not the answer you were hoping for. but hopefully helpful.
Thanks for your help Dude, I guess I'll be using the Pollak switch.
 

SirRobyn0

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Thanks for your help Dude, I guess I'll be using the Pollak switch.
Sorry about that. I knew we had done it I just didn't remember that we were buying a different switch. Though you might be disappointed to be running the pollak switch you'll be very happy with the reliability of that system.
 

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