Dual Tank Issues

[mlmx52002]

Hi,

First post here. I have a 79 C20 with dual tanks. The problem is they don't work. What the previous owner told me, since I just bought the truck back in July is that it is "stuck" on the right hand tank. He found out the hard way and switched it and it didn't switch. Apparently the switch on the dash switches the gas gauge, but only that. The gas gauge functions with both tanks. So my question is where do I start in trying to fix it? It'd be wonderful to use the dual tanks as the 350 4 speed gets  I think about 10 at best.

Thanks,

Joe

[Irish_Alley]

http://www.autozone.com/autozone/parts/1979-Chevrolet-C10-1-2-ton-P-U-2WD/Fuel-Tank-Selector-Valve/_/N-imf3zZ8ve9x?filterByKeyWord=fuel+tank+valve&fromString=search

[shufflekidd]

I have the 87 Silverado also. If you remember, there was a recall/ on the dual tank models due to safety issues with exploding or burning "side saddle" dual tanks. Most original owners were notified, and took the trucks in to have it fixed. On the truck I inherited, I still have documentation on the "fix", which the Chevy mechanics did. It was simply disabling/removing the second fuel pump relay, thats all they did. Unplugged the relay from the harness and removed it. Chances are, you might be able to install and plug up a new relay and both tanks will work if the "disabled" tank pump is still functioning. Be aware that any old fuel or varnish in the unused,"disabled" tank from the fix will only gum up your fuel system and destroy the tbi pressure regulator, so if you decide to pursue using dual tanks, you will probably have to disassemble tanks and clean it thoroughly, as well as blow and clean its fuel and return lines before even testing it.   

[Grim 82]

He has a 79. It won't have fuel pump relays or a fuel pressure regulator.

http://www.autozone.com/autozone/parts/1979-Chevrolet-C10-1-2-ton-P-U-2WD/Fuel-Tank-Selector-Valve/_/N-imf3zZ8ve9x?filterByKeyWord=fuel+tank+valve&fromString=search

^^This.

[mlmx52002]

Thanks for the help guys, but the darn thing wouldn't pass our lovely CA emissions, so I have since gotten rid of the sucker. It needed at most a rebuilt carb and possibily a cat.

Joe

[Captkaos]

Side note, there was NO recall on any trucks for the bogus "exploding" side tanks.
There was only a voucher from GM that would allow you $1000 against the purchase of a new vehicle.

[VileZambonie]

I have the 87 Silverado also. If you remember, there was a recall/ on the dual tank models due to safety issues with exploding or burning "side saddle" dual tanks. Most original owners were notified, and took the trucks in to have it fixed. On the truck I inherited, I still have documentation on the "fix", which the Chevy mechanics did. It was simply disabling/removing the second fuel pump relay, thats all they did. Unplugged the relay from the harness and removed it. Chances are, you might be able to install and plug up a new relay and both tanks will work if the "disabled" tank pump is still functioning. Be aware that any old fuel or varnish in the unused,"disabled" tank from the fix will only gum up your fuel system and destroy the tbi pressure regulator, so if you decide to pursue using dual tanks, you will probably have to disassemble tanks and clean it thoroughly, as well as blow and clean its fuel and return lines before even testing it.   

Yeah your info is WAY off here. You think GM would recall a truck and just say we're going to abandon a tank on you have a nice day? There is no second fuel pump relay so I'd love to see your documentation on the "fix"

[shufflekidd]

Yeah okay, maybe in your state there were no issues with gm dual saddles, but here in Tennessee, i know of at least two guys, including my grandfather, who took the trucks in and the gm mechanics "disabled" the right side tank, saying it was fixed, and they got the 1000 buck bonus on possible next purchase, which neither of them took, as they were not happy with the service they got on the first trucks. Just sayin!

[756man]

First off how do you think disabling 1 tank would make it safer? Second you didn't need to take your truck in to a dealer in order to get the $1000 off certificates. They sent me 2 and I had already sold 1 of the trucks.

[VileZambonie]

Yeah okay, maybe in your state there were no issues with gm dual saddles, but here in Tennessee, i know of at least two guys, including my grandfather, who took the trucks in and the gm mechanics "disabled" the right side tank, saying it was fixed, and they got the 1000 buck bonus on possible next purchase, which neither of them took, as they were not happy with the service they got on the first trucks. Just sayin!

You're misinformed however you state you have documentation so please provide proof. You say you have documentation so let's see it please....Just sayin!

[mnz28]

I thought the issue was side impact crashes and the tank could leak.

[Irish_Alley]

I don't honk the leak you should worry about but the fire ball lol.

[VileZambonie]

I don't honk the leak you should worry about but the fire ball lol.

Are you sure you don't honk the leak?

[Irish_Alley]

I try not to at least lol. when I start typing on the cell phone the droid its little slower than me so by time I finished typing the first line its still trying to type the first word so I don’t get to see what I type unless I proof read and that I don’t

[VileZambonie]

lol, I have the EVO and it suggests wrong words on me all the time.