• Welcome to ClassicBroncos! - You are currently viewing the forums as a GUEST. To take advantage of all the site features, please take a moment to register. It's fast, simple and absolutely free. So please join our community today!
    If you have problems registering or can't log into your account, please contact Admin.

eliminate auxillary fuel tank

lasadoor

Sr. Member
Joined
May 22, 2008
Messages
421
Loc.
San Diego
i would like to remove the aux tank and run a new line from main tank to fuel pump. I'm on the fence about replacing aux tank in future so I plan to keep any decent looking parts. Are there any parts I should leave in place or can I run one line from tank to pump? And what size fuel line should I use (stock tank, mechanical pump)? what about holding the line to the frame?
 

half cab

Contributor
Guru Bronco
Joined
Dec 8, 2010
Messages
16,306
I would just plug off the aux line and leave everything in place(keep valve switched to main) sence you may replace the aux tank in the future.What ever you do don't plug off the evap/charcoal can. line or you will be sitting at the gas pump along time trying to fill up.
 

OX1

Bronco Guru
Joined
Aug 26, 2003
Messages
3,458
i would like to remove the aux tank and run a new line from main tank to fuel pump. I'm on the fence about replacing aux tank in future so I plan to keep any decent looking parts. Are there any parts I should leave in place or can I run one line from tank to pump? And what size fuel line should I use (stock tank, mechanical pump)? what about holding the line to the frame?

If your not sure that you might put it back, just leave stock line and don't switch valve to aux position. If you are pulling all the lines out no matter what, I'd use 3/8 steel (or aluminum) line with short rubber connections at fuel tank and pump. Also acceptable to put a short rubber section in center of fuel line (somewhere well protected against abrasion, especially if you wheel it), only if you have to, to get it to fit.

See this thread also, as many have used some form of plastic line (this thread also details suggestions for frame clips).

http://classicbroncos.com/forums/showthread.php?t=206372
 

bronconut73

Bronco Guru
Joined
Aug 7, 2012
Messages
9,916
3/8 to 1/2 inch insulated clamps screwed to the frame with self tappers holding Earls stainless steel braided -6 AN fuel line from tank to pump.
 

75junebug

Sr. Member
Joined
Jan 10, 2008
Messages
587
Loc.
NW Houston Tx
BC broncos has a 3/8 fuel line kit with frame fasteners and all. I would bypass the whole fuel selector due to possible air/fuel leaks. Keep the components for the aux tank. Consider getting a 23 gal tank for the rear, and maybe use the aux tank as an emergency transfer tank. You could do this by simply routing a switched electric fuel pump and line back to a return line/ventline found on the 23 gal aftermarket tanks.
 

TBS-POPS

Bronco Guru
Joined
Jun 16, 2007
Messages
1,388
Loc.
valley springs, ca
I would just plug off the aux line and leave everything in place(keep valve switched to main) sence you may replace the aux tank in the future.What ever you do don't plug off the evap/charcoal can. line or you will be sitting at the gas pump along time trying to fill up.

The evap/char system has nothing to do with venting the tank to aid in fuel fill ups. Thats what the 1/2'' vent line is for comming out of the later tanks was for. The early tanks had a prob because this vent hose was absent. The 1/8'' spaghetti lines for the evap system would not flow enough air to vent the tank upon fill up.

Run 3/8'' line if you can then you dont have to worry about any fuel supply problems in the future. Rubber dipped clamps and self tappers to frame hold nice.
 

half cab

Contributor
Guru Bronco
Joined
Dec 8, 2010
Messages
16,306
The evap/char system has nothing to do with venting the tank to aid in fuel fill ups. Thats what the 1/2'' vent line is for comming out of the later tanks was for. The early tanks had a prob because this vent hose was absent. The 1/8'' spaghetti lines for the evap system would not flow enough air to vent the tank upon fill up.

Run 3/8'' line if you can then you dont have to worry about any fuel supply problems in the future. Rubber dipped clamps and self tappers to frame hold nice.

I'm only speaking from my own experence....


My cannister line on my '76 got blocked just under the pass floor where it crosses over and up the frame to the firewall...Hardly would fill up at the station....check the filler neck return and it was ok...unstopped the charcoal can line and all was well???

I don't know...like I said"speaking from my own experences"

Also I have over filled before and had gas spill just past the T where they (aux/main/evap) lines meet cause of bad hose9cracked),but would gas go up this far in the cannister line?
 
Last edited:

patterdale

Bronco Guru
Joined
May 24, 2010
Messages
1,246
Why would you want to limit your range so much? Unless you replace the main with a 23 gallon tank you can only go about 150 miles. If money is a problem in replacing the tank just pull it and plug the lines untill you replace it. I would give my left arm for and Aux tank as Elmer is an original stock 12? gallon tank with no auxillary.
 
Top