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Author Topic: Eliminate rear tank?  (Read 3890 times)

K30_dump

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Eliminate rear tank?
« on: November 02, 2011, 10:18:23 AM »
Hello all,

I know there have been a few threads/posts on this lately, but I figured I'd start my own (as some on other forums get pretty excited about "thread-jacking") :).

Purchased an '01 HD over the summer. 6.5, 4L80E, 159.5" wb (dual tanks of course :(). I am considering eliminating the rear tank, as I don't plan to ever drive the truck long distances. Don't get me wrong, I think the rear tank may be a nice option if ever needed. Unless kept full though, I fear it may cause condensation problems, etc. Plus, if left empty, I only have half of the fuel gauge to use (as we know). Also not 100% sure if the sender is good, as it is reading 30 ohms even though it's nearly empty :(...

So, I am considering deleting it. I know doing away with it is simple, but I don't want an inaccurate gauge. Looking at the GM schematics, it LOOKS like all I need to do for an accurate gauge reading is to connect the blue/white wire from the front sender directly to the purple wire at the gauge. Sounds easy enough, but has anyone ever successfully done it?

Should I try to eliminate it, or fill both ($$) and just top up the rear when filling? I assume the front tank would be kept full if the system is functioning properly?

Thanks,

Joe
« Last Edit: November 02, 2011, 10:24:03 AM by K30_dump »

mrhd

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Re: Eliminate rear tank?
« Reply #1 on: November 02, 2011, 11:21:00 AM »
I really hope someone can help u out kuz im in the same boat as u are.....i got rid of my rear tank and hooked up an aftermarket fuel level gauge right to the sending unit and when it reads 1/2 a tank it runs outta gas

mrhd

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Re: Eliminate rear tank?
« Reply #2 on: November 02, 2011, 11:57:44 AM »
I was thinking of swapping the sending unit out with one from a normal 3500

mrhd

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Re: Eliminate rear tank?
« Reply #3 on: November 07, 2011, 01:51:08 AM »
OK man here's what my thought was......... what if we replaced the fuel level gauge arm inside the tank with one from another truck it should send the right ohms the the gauge so that it would be using the hole gauge instead of just the second half of it

ED-NY

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Re: Eliminate rear tank?
« Reply #4 on: November 07, 2011, 10:38:11 AM »
Here is a link outlining the install of an aftermarket tank sending unit:

http://www.gilmoredist.com/howto_guides/instruction_sheets/Datcon_SW_Sheets/Adjustable_Fuel_Sender.PDF

Basically, you need to position the rheostat "approx" half way from the top and bottom of tank. The float should also be positioned half way. In the half-way position the rheostat should read 45 ohm (for a 0-90 ohm unit).

Also..With sending unit in hand and with float at the lowest level... move the float slowly upward. It should begin at 0 ohm and increase up to the 90 ohm mark as the float is lifted to the top position.

FYI: Pre 1965 GM's use a 0-30 ohm rheostat in the tanks, the one in my 34 Chevy reads 37 ohm when full which gives me a way past full reading on the dash fuel gauge when the tank is full.


Ed

someotherguy

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Re: Eliminate rear tank?
« Reply #5 on: November 07, 2011, 11:44:01 AM »
Hey Ed- semi-related, since I'm going to remove this aux side tank from my '95, I wonder what I need to do with the sender on my main tank (factory 22 gallon driver side mount)?

Currently both tanks are still on the truck but I have the harness to the frame-mount pump disconnected; the truck has been running fine and showing around 1/2 tank on the gauge.  Last night while flushing out the cooling system to add fresh antifreeze, it started to stumble and finally crapped out on me.  I'm wondering if I'm out of gas, and if so, that points to me needing to swap out the sender or adjust it somehow.

Richard
06 Silverado ISS / 06 Silverado SS / 06 300C SRT8

ED-NY

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Re: Eliminate rear tank?
« Reply #6 on: November 07, 2011, 04:34:38 PM »
Hey Ed- semi-related, since I'm going to remove this aux side tank from my '95, I wonder what I need to do with the sender on my main tank (factory 22 gallon driver side mount)?

Currently both tanks are still on the truck but I have the harness to the frame-mount pump disconnected; the truck has been running fine and showing around 1/2 tank on the gauge.  Last night while flushing out the cooling system to add fresh antifreeze, it started to stumble and finally crapped out on me.  I'm wondering if I'm out of gas, and if so, that points to me needing to swap out the sender or adjust it somehow.

Richard

Richard

Kinda reminds me of my recent Corvette situation, installed a new electric pump and sock. The problem was that I put the sock on wrong. The float would not drop properly because it hit the sock...showed a half tank even when empty. Had to remove the sending unit again and position the sock so the float would clear it and allow the full range of movement.

You may just need to pull it, check for movement range and ohm it out?

Ed

someotherguy

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Re: Eliminate rear tank?
« Reply #7 on: November 07, 2011, 05:16:08 PM »
Oh I dunno...it's such a chore to remove the sender...

...while there's no bed on the truck.  ;) ;D

Got some other work to do on the truck today, I'll probably pop the sender out and have a look.  Actually I kind of hate to do it because I bet it's the original parts and the O-ring will be hard as a rock, so I'll find myself headed back to the auto parts.

Richard
06 Silverado ISS / 06 Silverado SS / 06 300C SRT8

 


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