1/4" fuel line between tank and pump problems?

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   Has anyone ever had problems with the stock 1/4" stock size fuel line between the gas tank and the fuel pump being too restrictive?  I am just thinking out loud.  I have my buddy John finishing up some items on my project, and he is seeing, among others, some gas delivery issues.  When John went to drain the tank, fuel barely poured out of the stock 1/4" flared fitting on the bottom of the tank.  John was thinking this fitting (welded/brazed to the tank) might be too restrictive.  He was thinking maybe is should be 5/16" or even 3/8"?  Has anybody been down this rabbit hole before?
We have a pinhole leak on a weld on the tank, so I have picked up the tank to have this fixed.  I just thought I'd ask now whilst the tank was out of the vehicle.

Thanks.

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bosshoff Members Profile Send Private Message Find Members Posts Add to Buddy List Member Joined: 30 Apr. 2012 Location: chicagoland Status: Offline Points: 206	Post Options Post Reply Quote bosshoff Report Post Thanks(0) Quote Reply Topic: 1/4" fuel line between tank and pump problems? Posted: 26 Oct. 2021 at 4:50pm
	Has anyone ever had problems with the stock 1/4" stock size fuel line between the gas tank and the fuel pump being too restrictive? I am just thinking out loud. I have my buddy John finishing up some items on my project, and he is seeing, among others, some gas delivery issues. When John went to drain the tank, fuel barely poured out of the stock 1/4" flared fitting on the bottom of the tank. John was thinking this fitting (welded/brazed to the tank) might be too restrictive. He was thinking maybe is should be 5/16" or even 3/8"? Has anybody been down this rabbit hole before? We have a pinhole leak on a weld on the tank, so I have picked up the tank to have this fixed. I just thought I'd ask now whilst the tank was out of the vehicle. Thanks.
	Chop chop

windyhill Members Profile Send Private Message Find Members Posts Add to Buddy List Member Joined: 14 Mar. 2009 Location: North East PA Status: Offline Points: 1395	Post Options Post Reply Quote windyhill Report Post Thanks(0) Quote Reply Posted: 26 Oct. 2021 at 5:10pm
	Interesting you should ask, I swapped in a v6 many years ago and had the stock line and tank. I always had issues with it running. When I recently converted it to EFI I ran a new 5/16 line to the tank and drilled out the hole bigger on the tank. It runs great now. I'm not sure how much the fuel line was the issue, but it certainly helped. I drilled out the hole in the tank, (There is a little tube that sticks up inside the tank to help with junk so be carful) I looked at a 5/16" line and opened the hole to that size, then I put a 1/4 to 5/16 adapter on and ran a new 5/16 hard line. Edited by windyhill - 26 Oct. 2021 at 5:13pm
	'48 CJ2A '53 CJ3B '59 CJ6 '65 CJ5 '67 CJ5

Rus Curtis Members Profile Send Private Message Find Members Posts Add to Buddy List Member Joined: 25 Mar. 2010 Location: Alabama Status: Offline Points: 1733	Post Options Post Reply Quote Rus Curtis Report Post Thanks(0) Quote Reply Posted: 26 Oct. 2021 at 8:49pm
	As mentioned, the fuel line connection (flared) has a pick up tube. fuelpickup.jpg (800×600) (cj3a.info) Since the fuel has to go uphill before exiting, I'd assume (possibly in error) that it wouldn't drain very well. The other plug is the drain plug (it's also in the above image). What I'd be more suspicious of is debris or trash in the tank that might restrict flow. Directly to your question, early on? Yes. After fixing that problem, no. It may be worth considering replacement.
	Rus Curtis Alabama 1954 CJ3B Bantam T3-C

bosshoff Members Profile Send Private Message Find Members Posts Add to Buddy List Member Joined: 30 Apr. 2012 Location: chicagoland Status: Offline Points: 206	Post Options Post Reply Quote bosshoff Report Post Thanks(0) Quote Reply Posted: 27 Oct. 2021 at 12:39pm
	Rus, The tank is new so debris should not really be an issue. I'm working through other issues regarding the tank. I had to modify a CJ2A tank to a top fill. One of the welds on the side of the tank had a leak/drip that needs to be addressed by my welder. My buddy John is more of a Bronco guy, so the CJ stuff is a bit new to him. Me, I just don't know stuff like this, so I ask you guys.
	Chop chop

Bruce W Members Profile Send Private Message Find Members Posts Add to Buddy List Member Joined: 29 July 2005 Location: Northeast Colorado Status: Offline Points: 9652	Post Options Post Reply Quote Bruce W Report Post Thanks(0) Quote Reply Posted: 27 Oct. 2021 at 1:28pm
	That little trickle of fuel may have seemed pretty puny, but I certainly hope your engine doesn’t use it up as fast as that. Don’t forget, the pump will be helping. Ford used 5/16” line on their four-barrel V8’s right up until the end of the carburetor era. Engines twice (and more) the displacement of ours with only a bit larger line. I run my 134’s pretty hard (WFO) for extended distances at times, and have never run out of fuel delivery capacity, even when experimenting with a 2-barrel carb. Rus, after the fuel goes uphill into the “shepherds crook” inside the tank, it goes immediately downhill which creates a siphon effect, which counterbalances the uphill pull, and even moreso because it goes downhill farther than it goes uphill. BW
	It is NOT a Jeep Willys! It is a Willys jeep. Happy Trails! Good-bye, Good Luck, and May the Good Lord Take a Likin' to You! We Have Miles to Jeep, Before We Sleep.

bosshoff Members Profile Send Private Message Find Members Posts Add to Buddy List Member Joined: 30 Apr. 2012 Location: chicagoland Status: Offline Points: 206	Post Options Post Reply Quote bosshoff Report Post Thanks(0) Quote Reply Posted: 27 Oct. 2021 at 2:38pm
	Bruce W, Thanks for the perspective. That makes a lot of sense.
	Chop chop

Ron D Members Profile Send Private Message Find Members Posts Add to Buddy List Member Joined: 27 Oct. 2019 Location: South Carolina Status: Offline Points: 1446	Post Options Post Reply Quote Ron D Report Post Thanks(0) Quote Reply Posted: 27 Oct. 2021 at 3:45pm
	If the fuel pump is putting out the correct pressure and volume specified by the tests in the manual, why would the factory-sized fuel line and fittings be a problem? It seems to me that you could hook up a fire hose size line to the pump and it wouldn't make a difference. Edited by Ron D - 27 Oct. 2021 at 3:47pm
	1951 M38 1951 M100

bosshoff Members Profile Send Private Message Find Members Posts Add to Buddy List Member Joined: 30 Apr. 2012 Location: chicagoland Status: Offline Points: 206	Post Options Post Reply Quote bosshoff Report Post Thanks(0) Quote Reply Posted: 27 Oct. 2021 at 3:56pm
	Ron D, I guess it wouldn't make a difference if everything on my 75 year old beater was original! I find stuff all the time that has been changed or added over the years. A few quick examples, my Ross steering box is much larger than stock and is from a late 1950's model. My oil bath air filter has a larger than stock inlet, and looks slightly different, which tells me it is not OEM CJ2A. I have no idea if my carb is original, or if it came of a different vehicle, etc. I try and not assume anything when dealing with my rig.
	Chop chop

Ron D Members Profile Send Private Message Find Members Posts Add to Buddy List Member Joined: 27 Oct. 2019 Location: South Carolina Status: Offline Points: 1446	Post Options Post Reply Quote Ron D Report Post Thanks(0) Quote Reply Posted: 27 Oct. 2021 at 4:03pm
	I can certainly understand that Boss. Because you didn't say otherwise, I made an assumption that you have a stock set up, or at least that you know what you have. Sorry about that! Edited by Ron D - 27 Oct. 2021 at 4:04pm
	1951 M38 1951 M100

bosshoff Members Profile Send Private Message Find Members Posts Add to Buddy List Member Joined: 30 Apr. 2012 Location: chicagoland Status: Offline Points: 206	Post Options Post Reply Quote bosshoff Report Post Thanks(0) Quote Reply Posted: 27 Oct. 2021 at 4:24pm
	No problem Ron, I didn't take any offense.
	Chop chop

Bruce W Members Profile Send Private Message Find Members Posts Add to Buddy List Member Joined: 29 July 2005 Location: Northeast Colorado Status: Offline Points: 9652	Post Options Post Reply Quote Bruce W Report Post Thanks(0) Quote Reply Posted: 27 Oct. 2021 at 8:04pm
	boss, we are happy to help you figure out what you have and to help you get it back to original or wherever you want it. BW
	It is NOT a Jeep Willys! It is a Willys jeep. Happy Trails! Good-bye, Good Luck, and May the Good Lord Take a Likin' to You! We Have Miles to Jeep, Before We Sleep.