Gas Tank Switch 84 GMC

[rainman15]

Good Day,

I finally got back down to NC to pick up the 84 GMC High Sierra I inherited from my father in law. The drivers gas tank is leaking, I don't have time to swap it because I need to take the truck back to NYC this week and can't get a new tank that fast. I could get by just using the passenger tank for the trip then installing a new drivers tank once I get there. Just my luck the dang switch isn't swapping tanks like it is supposed to.  The passenger tank is full of gas but the gauge never moves when I swap it.  Any ideas?  Chris

[Captkaos]

Check for power at the switch and power at the switching valve to make sure those pieces are getting power to them.

[VileZambonie]

Are you fully depressing the switch? http://forum.73-87chevytrucks.com/smforum/index.php?topic=9072.0

[rainman15]

Thanks for the link. That is helpful.  I can't figure out how to get the switch out of the dash and I don't want to break it. Which direction should I pull? Does the trim ring come off first or is it one piece?  Also,where is the switching valve located?  84 4x4 short bed GMC.

[low budget]

If all else fails, how bad is it leaking?  Can you put a temp patch on it?  Auto Zone sells stuff to patch it...

[rainman15]

I guess it is leaking near a gallon a day.  I've had it parked in the hospital parking lot since 8:50 am, it's 4:20pm now and it has a puddle about 2 feet across under it.  Now the passenger tank is dripping too, just not as bad.  I seriously need to park this thing until I can get new tanks ordered, but I have no other way back to NYC and I don't want to waste the money I could use for new gas tanks on another plane ticket.

[low budget]

IMO, fill it up and drive it home.  It will go thru at least a tank anyway getting it home

[VileZambonie]

Push the tank switch from the dash from the inside or it will probably break. The switching valve is under the passenger side frame rail near the back of the cab. Since it's carbureted you can easily bypass the whole system by just running a new fuel line from the "good" tank to the main carb feed line.

[Blue 82]

My switch acts up once in a while
Push and hold it for a second or two, between tanks 3 or 4 times.
If that don't work, check the plug with 2 green wires coming out of the firewall, behind the drivers side valve cover
and make sure it's plugged in. That goes to the tank selector valve. I knocked it loose one time and could not switch tanks.

Permatex makes a gas tank repair epoxy, I fixed a dime size hole about a year ago and it's still holding. $10 at any auto parts store, but make sure to get the permatex brand.

[rainman15]

Thanks for the help guys.

I'm pretty determined to replace the tanks rather than repair. The tanks are quite rusty as are the straps that hold them up. First thing Monday I'm calling to order 2 tanks and strap kits.  Once I'm down there to replace them I'll use my meter to make sure that the switching valve is getting power and work my way back through the circuit to the switch, now that I know where the circuit routes through.

I really love my truck.  It isn't perfect, but it is a keeper.

[Irish_Alley]

i would say use a boat tank in the bed but a 5 gal you would have to stop every  50 miles or so lol