Author Topic: Fuel return hose  (Read 2804 times)

Offline 1979C20

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  • Kyle Taulton.
Fuel return hose
« on: February 12, 2011, 03:37:25 PM »
Any chance I can get a diagram of the fuel hoses for dual tanks on the truck in my sig? When I dropped my passenger tank a few months ago to check the sending unit, my hose was cracked and dry rot. So, I left what I believe is the return hose off. And I just recently started going through a lot of fuel in the past month, I crawled under my truck 2 weeks ago and found the my to pump hose on my tank selector was leaking, so I tightended the hose clamp. Now, last night I lost almost a half tank driving ten miles. I crawled under my truck and there was fuel sprayed all over my frame rail. And it looks like its coming from the steel line for the return hose?
1979 SCLB C20 Q-jet 350 SM465 14b F.F. 4.10 G80
1989 GMC Suburban V2500 TBI350 TH400 4in lift 35's 14b SF

Offline Grim 82

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Re: Fuel return hose
« Reply #1 on: February 12, 2011, 07:17:48 PM »
So, I left what I believe is the return hose off. And I just recently started going through a lot of fuel

Replace the fuel line. Whatever gas the motor is not using is being shed back through the return hose and you are spraying it on the ground. I don't have a diagram of the routing, but from the pump you have a feed and a return back to the switch valve, and then a feed and return to the left tank, and a feed and return to the right tank. The bigger 3/8" fittings are the feed line and the smaller ones are the return. If you have vent lines to the cannister they will be the smallest of the 3 different sizes, and they are just teed together and run to the charcoal can seperate of the valve.
Give a man a gun, and he might rob a bank. Give a man a bank, and he might rob the world.

Offline 1979C20

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Re: Fuel return hose
« Reply #2 on: February 12, 2011, 11:48:54 PM »
Well, theres only 2 lines on my fuel pump. From the selector and to thr carb
1979 SCLB C20 Q-jet 350 SM465 14b F.F. 4.10 G80
1989 GMC Suburban V2500 TBI350 TH400 4in lift 35's 14b SF

Offline Grim 82

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Re: Fuel return hose
« Reply #3 on: February 13, 2011, 11:26:20 AM »
So where is the line that you left off? If you put it back on you should be good to go.
Give a man a gun, and he might rob a bank. Give a man a bank, and he might rob the world.

Offline 1979C20

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Re: Fuel return hose
« Reply #4 on: February 13, 2011, 03:05:03 PM »
I need to finish bolting my new engine mounts back in today so ill snap a pic. Can I just cap it? Vb I really dont want to drop the tank again.
1979 SCLB C20 Q-jet 350 SM465 14b F.F. 4.10 G80
1989 GMC Suburban V2500 TBI350 TH400 4in lift 35's 14b SF

Offline Grim 82

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Re: Fuel return hose
« Reply #5 on: February 13, 2011, 03:23:00 PM »
I'm not really sure what you have there. All of the pumps I have seen have 3 ports; a feed, return, and one to the carb. Yours may be different because it's a different year, I don't know. I don't think you can get away with just capping it but I can't say for sure. How many ports are on the selector valve?

I would put it back the way it was before it started giving you trouble, even if that means dropping the tank again. That sucks but I think it's the right way to go.
Give a man a gun, and he might rob a bank. Give a man a bank, and he might rob the world.