Go Back   The Ford Barn > General Discussion > Early V8 (1932-53)

Sponsored Links (Register now to hide all advertisements)

Reply
 
Thread Tools Display Modes
Old 08-15-2018, 04:26 AM   #1
JD
Member
 
Join Date: May 2010
Location: Christchurch New Zealand
Posts: 43
Default 1934 pickup leaking fuel from filler neck

My 1934 pickup is leaking fuel from the filler neck area. I knew the truck had this problem when I bought it and I assumed a leaky seam on the tank or a leak in the filler neck so I removed the tank and had it checked out. There was a slight leak at the seam near the filler pipe and this was resoldered. The tank was cleaned and leak tested and I re-installed it in the truck.

When driving it after that I noticed wet fuel stains on the rear guard below the filler neck so I took it for a drive with my son following in another vehicle. He soon got me to pull over and stop because fuel was sloshing out every time the truck went around a corner. I suspected the seal in the locking gas cap so replaced it with a rubber cap (small vent hole in centre) but this made no difference. This occurred with a full tank. I tried another drive with the tank half full but the problem persisted. I have since borrowed an original style fuel cap from a friend's 34 sedan but again this made no difference, in fact fuel was spilling out past the cap before I even got to the end of the driveway. There are no issues with this cap when in use on the sedan.

It's almost as if the fuel is under pressure but as far as I know this is not a pressurised system. Could it be a broken or missing baffle inside the tank? Any suggestions would be appreciated.

John Dudson
JD is offline   Reply With Quote
Old 08-15-2018, 04:48 AM   #2
1934
Senior Member
 
1934's Avatar
 
Join Date: Jul 2010
Location: Quebec, Canada
Posts: 379
Default Re: 1934 pickup leaking fuel from filler neck

I've had this same problem on my '34 sedan. Tried several different caps, made gaskets from cork, rubber- nothing seems to help. The only thing that does help, (a bit), is a little grease on the gasket where it meets the filler neck top. It still leaks, but not as much. Good luck and let us know if you resolve the problem.
BTW, the cap should not be vented.
Doug.
1934 is offline   Reply With Quote
Sponsored Links (Register now to hide all advertisements)
Old 08-15-2018, 10:44 AM   #3
cmbrucew
Senior Member
 
cmbrucew's Avatar
 
Join Date: Dec 2010
Location: North of sandy ago, CA.
Posts: 1,891
Default Re: 1934 pickup leaking fuel from filler neck

Doug
If you should use a vented cap for expansion of fuel on a hot day, and consumption of fuel while driving. Do not fill your tanks so full and they will not leak.
Bruce
__________________
Works good
Lasts long time
cmbrucew is offline   Reply With Quote
Old 08-15-2018, 11:36 AM   #4
50fordcoupeman
Senior Member
 
50fordcoupeman's Avatar
 
Join Date: Mar 2016
Location: LaGrande Oregon
Posts: 765
Default Re: 1934 pickup leaking fuel from filler neck

My father had this problem on a little jeep universal he called it (military). Tank was under the drivers seat. He used JB water weld. Never leaked again.
50fordcoupeman is offline   Reply With Quote
Old 08-15-2018, 03:28 PM   #5
JD
Member
 
Join Date: May 2010
Location: Christchurch New Zealand
Posts: 43
Default Re: 1934 pickup leaking fuel from filler neck

Quote:
Originally Posted by 50fordcoupeman View Post
My father had this problem on a little jeep universal he called it (military). Tank was under the drivers seat. He used JB water weld. Never leaked again.
Where he did he apply the weld?
JD is offline   Reply With Quote
Old 08-15-2018, 03:36 PM   #6
JD
Member
 
Join Date: May 2010
Location: Christchurch New Zealand
Posts: 43
Default Re: 1934 pickup leaking fuel from filler neck

Sponsored Links (Register now to hide all advertisements)
Quote:
Originally Posted by cmbrucew View Post
Doug
If you should use a vented cap for expansion of fuel on a hot day, and consumption of fuel while driving. Do not fill your tanks so full and they will not leak.
Bruce
Bruce it leaks even when the tank is half full or less
JD is offline   Reply With Quote
Old 08-15-2018, 05:52 PM   #7
Mart
Senior Member
 
Mart's Avatar
 
Join Date: May 2010
Location: Solihull, England.
Posts: 7,416
Default Re: 1934 pickup leaking fuel from filler neck

I fixed this on my 33 coupe.

I fitted a thick rubber seal from a modern cap to the cap and that stopped the leaking.

But I needed to create a vent (non stock sender unit). I took a piece of 3/16 steel brake line and threaded one end 10-32 UNF. I fitted a nut to this and used it in place of one of the sender screws. the pipe was bent with a couple of corkscrew turns and has a fuel filter attached to it. As far as I can tell, it does not leak fuel.

The thick rubber seal makes the cap tight to remove and refit, but it is do-able using two hands to get it started when loosening and tight when refitting.

Prior to this I had made up a sort of baffle system in the filler neck, and modified the cap to seal against the baffles in an attempt to stop fuel sloshing out. This on it's own was not enough.

The combo of the thick seal and the baffles did the trick.

I think the mention of the jb weld above was regarding the seam that got soldered, nothing to do with the cap.

Mart.
Mart is offline   Reply With Quote
Old 08-15-2018, 06:15 PM   #8
Cool 33
Senior Member
 
Cool 33's Avatar
 
Join Date: May 2010
Location: Forney, Tex.
Posts: 123
Default Re: 1934 pickup leaking fuel from filler neck

Seeing as how it is a pickup it could be that the lead washer seal where the neck is screwed in the tank is bad or the gland nut has worked loose. Several suppliers have the lead washer but I have found that some reproduction washers are too thin and some are too small in diameter and will leak even when the neck is tight.
Cool 33 is offline   Reply With Quote
Old 08-15-2018, 06:27 PM   #9
1934
Senior Member
 
1934's Avatar
 
Join Date: Jul 2010
Location: Quebec, Canada
Posts: 379
Default Re: 1934 pickup leaking fuel from filler neck

Quote:
Originally Posted by JD View Post
Bruce it leaks even when the tank is half full or less
Ditto. I never fill the tank really full. Anything over half full and it will leak going around corners or on rough roads.
1934 is offline   Reply With Quote
Old 08-15-2018, 06:41 PM   #10
deuce_roadster
Senior Member
 
deuce_roadster's Avatar
 
Join Date: Oct 2011
Location: Shelton, WA
Posts: 2,950
Default Re: 1934 pickup leaking fuel from filler neck

Yeah, the lead washer is more likely the problem. Compare new ones with the end of your filler neck where the wrench tightens it into the tank to make sure it will seal the whole circumference, maybe buy 2 lead washers if they have cheapened up the item by making it thin.
deuce_roadster is offline   Reply With Quote
Old 08-15-2018, 06:55 PM   #11
Talkwrench
Senior Member
 
Talkwrench's Avatar
 
Join Date: Aug 2012
Location: Perth, Western Australia
Posts: 2,655
Default Re: 1934 pickup leaking fuel from filler neck

Does the filler neck screw into the tank, I assume it does like a 35 [?] was the lead seal replaced ?
Mine still leaks too , though I dont have the original more upright filler neck. I have a plastic filler neck that Ive squashed down the end of and that sits in the filler neck of the tank and then cap goes on. Helps a little and I also have a sweat band that put on the outside so I dont spray other cars while going around corners I try not to go over 2/3 full.
__________________
"Came too close to dying to stop living now!"
Talkwrench is offline   Reply With Quote
Old 08-16-2018, 12:02 AM   #12
my4dv8
Senior Member
 
Join Date: Aug 2010
Location: New Zealand
Posts: 968
Default Re: 1934 pickup leaking fuel from filler neck

Hi JD , havent seen you in awhile., i don’t remember fuel leaks at the cap on our 34 pickup which we sold. But have had issues on the 32 coupe. We used to put a bit of motorcycle tube over the cap an neck ,that worke mostly ok. Then we switched to an aftermarket cap with the V8 embossed in the top, no more leaks. Sorry dont know the brand but we bought it off Magoos.
my4dv8 is offline   Reply With Quote
Old 08-16-2018, 12:06 AM   #13
50fordcoupeman
Senior Member
 
50fordcoupeman's Avatar
 
Join Date: Mar 2016
Location: LaGrande Oregon
Posts: 765
Default Re: 1934 pickup leaking fuel from filler neck

JD......he applied where the neck went into the tank if I remember correctly.
50fordcoupeman is offline   Reply With Quote
Old 08-16-2018, 04:11 AM   #14
FlatheadTed
Senior Member
 
FlatheadTed's Avatar
 
Join Date: May 2010
Location: Auckland
Posts: 4,408
Send a message via AIM to FlatheadTed
Default Re: 1934 pickup leaking fuel from filler neck

Can you get under and wrap some tape around the joint over the wrench holes ,put lots on as a temporary test to see if that stops it if it does you then need to deal to the led washer
__________________
http://www.flatheadted.com



Disclaimer ,Copy right all rights reserved Posting in good faith for the benefit of the public ,
Cannot be used for litigation,
FlatheadTed is offline   Reply With Quote
Old 09-05-2018, 02:03 AM   #15
JD
Member
 
Join Date: May 2010
Location: Christchurch New Zealand
Posts: 43
Default Re: 1934 pickup leaking fuel from filler neck

Sorry I missed your reply; yes i will try the tape.

I have also been wondering about the possibility of a broken baffle?

John
JD is offline   Reply With Quote
Old 09-05-2018, 05:15 PM   #16
FlatheadTed
Senior Member
 
FlatheadTed's Avatar
 
Join Date: May 2010
Location: Auckland
Posts: 4,408
Send a message via AIM to FlatheadTed
Default Re: 1934 pickup leaking fuel from filler neck

OK John ,Baffle, I would think unlikely ,it has been mentioned if the tank was full and you could get splash out the neck or cap then running down, I think the pick up neck is higher than a sedan so less likely ,Ted
__________________
http://www.flatheadted.com



Disclaimer ,Copy right all rights reserved Posting in good faith for the benefit of the public ,
Cannot be used for litigation,

Last edited by FlatheadTed; 09-06-2018 at 05:28 AM.
FlatheadTed is offline   Reply With Quote
Old 09-10-2018, 03:04 PM   #17
Jack 34pu
Senior Member
 
Jack 34pu's Avatar
 
Join Date: May 2010
Location: State College, PA
Posts: 362
Default Re: 1934 pickup leaking fuel from filler neck

Check surface of neck where cap seats. I must have hit mine sometime ago with the gas pump nozzle. Put a slight dent in seating area and it leaked. Made a thicker rubber seal which helped.
Jack 34pu is offline   Reply With Quote
Old 09-12-2018, 03:29 PM   #18
JD
Member
 
Join Date: May 2010
Location: Christchurch New Zealand
Posts: 43
Default Re: 1934 pickup leaking fuel from filler neck

I ran a metal ruler / straight edge over the surface of the neck where the cap sits. It appears to be dead level.
JD is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Sponsored Links (Register now to hide all advertisements)


All times are GMT -5. The time now is 01:48 AM.