Notices
1973 - 1979 F-100 & Larger F-Series Trucks Discuss the Dentsides Ford Truck
Sponsored by:
Sponsored by: Moser

Leaky gas cap

Thread Tools
 
Search this Thread
 
Old May 16, 2008 | 02:21 PM
  #1  
OrangeJuice's Avatar
OrangeJuice
Thread Starter
|
More Turbo
Joined: Nov 2007
Posts: 703
Likes: 3
From: Western Washington
Smile Leaky gas cap

Hi everyone,

This has been a problem since I bought my truck. The aft gas cap seems to spill a little fuel from the cap after filling up. The cap is a vented locking cap and I'm thinking the gas is leaking through the vented hole on the back side and not so much around the rubber seal. I'm having to clean the real quarter panel quite often. I try not to top off this tank as it seems to help a bit. Has anyone else experienced this problem with their caps and is there a fix to the problem.

Thank You
 
Reply
Old May 16, 2008 | 02:25 PM
  #2  
81-F-150-Explorer's Avatar
81-F-150-Explorer
Post Fiend
Joined: Jul 2004
Posts: 8,786
Likes: 28
From: Northern California
Have you tried buying a new gas cap?
 
Reply
Old May 16, 2008 | 03:32 PM
  #3  
OrangeJuice's Avatar
OrangeJuice
Thread Starter
|
More Turbo
Joined: Nov 2007
Posts: 703
Likes: 3
From: Western Washington
yes, I have replaced it several times with the same results.
 
Reply
Old May 16, 2008 | 03:55 PM
  #4  
Ds7776's Avatar
Ds7776
Senior User
Joined: May 2003
Posts: 333
Likes: 0
From: South Dakota
Ive had this problem on my 70 F100 with an in cab gass tank its the gas vapors expanding and pushing gas up into the fill hose. Ive had no success in fixing my leak but it seems to help when I park it so that the driver side sits up higher. O reven parking in the shade and not filling up right before parking.
 
Reply
Old May 16, 2008 | 04:32 PM
  #5  
81-F-150-Explorer's Avatar
81-F-150-Explorer
Post Fiend
Joined: Jul 2004
Posts: 8,786
Likes: 28
From: Northern California
Originally Posted by OrangeJuice
yes, I have replaced it several times with the same results.
Have you tried putting a non-locking cap on the truck. Locking caps are notorious for leaking through the seal.

Also if your truck is equipped with an evaporation system, check to see if the hoses going to the charcoal canister is in good shape, and also check the vent on top of the tank. Make sure there are no blockages.

Also, it is a good idea, especially with trucks with evaporative systems, not to top off the gas tank. Fill it to the first shutoff only to prevent gas from entering the evap system and blocking it. In California it is ilegal to top off a gas tank for this reason.

Good luck.
 
Reply
Old May 16, 2008 | 05:07 PM
  #6  
czaroc's Avatar
czaroc
Senior User
Joined: Feb 2007
Posts: 381
Likes: 5
Can you even fill a pre '77 in Calif? I have to drive around to find the "old" style pumps to fill mine. I can't get the new style nozzles to work.
 
Reply
Old May 16, 2008 | 05:34 PM
  #7  
81-F-150-Explorer's Avatar
81-F-150-Explorer
Post Fiend
Joined: Jul 2004
Posts: 8,786
Likes: 28
From: Northern California
Originally Posted by czaroc
Can you even fill a pre '77 in Calif? I have to drive around to find the "old" style pumps to fill mine. I can't get the new style nozzles to work.
Yes but it's a pain in the you know where. The evaporation recovery on the gas station nozzle seals too well.

It's the same when you try and fill a gas can. Cant vent the air fast enough.


The best success I've had with my 1973, is to turn the gas nozzle upside down from normal. This keeps the nozzle from sealing 100% on the truck.

good luck.
 
Reply
Old May 17, 2008 | 12:08 AM
  #8  
OrangeJuice's Avatar
OrangeJuice
Thread Starter
|
More Turbo
Joined: Nov 2007
Posts: 703
Likes: 3
From: Western Washington
Thanks for the help everyone. This leaking problem has never happened with the front gas cap, always the rear. Not sure why. Maybe the design/angle of the front filler tube?....I don't know. I've even seen the fuel spewing out of the rear cap area after filling-up and making a right turn...Yikes! I have not tried a nonlocking gas cap especially now with the high cost of fuel. I guess I could try it, but I'm worried someone would have a field-day with the amout of fuel our trucks hold.

Thanks again everyone.
 
Reply
FTE Stories

Ford Trucks for Ford Truck Enthusiasts

story-0

Top 10 Ford Truck Tragedies

 Joe Kucinski
story-1

AEV FXL Super Duty - the Super Duty Raptor Ford Doesn't Make

 Brett Foote
story-2

Lobo Vs Lobo: Proof the F-150 Lobo Should Be Even Lower!

 Michael S. Palmer
story-3

Ford's 2001 Explorer Sportsman Concept Looks For a New Home

 Verdad Gallardo
story-4

10 Best Ford Truck Engines We Miss the Most!

 Joe Kucinski
story-5

2026 Shelby F-150 Off-Road: Better Than a Raptor R?

 Brett Foote
story-6

2027 Super Duty Carhartt Package First Look: 12 Things You NEED to Know!

 Michael S. Palmer
story-7

10 Most Surprising 2026 Ford Truck Features!

 Joe Kucinski
story-8

Top 10 Ford Trucks Coming to Mecum Indy 2026

 Brett Foote
story-9

5 Best / 5 Worst Ford Truck Wheels of All Time

 Joe Kucinski
Old May 17, 2008 | 11:08 AM
  #9  
Shamus's Avatar
Shamus
Senior User
Joined: Nov 2006
Posts: 182
Likes: 0
From: Oklahoma City
It truly sounds like that tanks vents are blocked.
 
Reply
Old May 17, 2008 | 02:02 PM
  #10  
OrangeJuice's Avatar
OrangeJuice
Thread Starter
|
More Turbo
Joined: Nov 2007
Posts: 703
Likes: 3
From: Western Washington
They may be. I'll have to check that.

Thanks
 
Reply
Old May 17, 2008 | 03:52 PM
  #11  
Ds7776's Avatar
Ds7776
Senior User
Joined: May 2003
Posts: 333
Likes: 0
From: South Dakota
It spews out when you turn could you tank supports straps or brackets be broke or hang lower on one side?
 
Reply




All times are GMT -5. The time now is 11:29 PM.

story-0
Top 10 Ford Truck Tragedies

Slideshow: Top 10 Ford truck tragedies.

By Joe Kucinski | 2026-05-18 19:34:33


VIEW MORE
story-1
AEV FXL Super Duty - the Super Duty Raptor Ford Doesn't Make

And it might be even better than that.

By Brett Foote | 2026-05-18 19:26:42


VIEW MORE
story-2
Lobo Vs Lobo: Proof the F-150 Lobo Should Be Even Lower!

Slideshow: Does lowering an F-150 Lobo RUIN the ride quality?

By Michael S. Palmer | 2026-05-18 19:20:37


VIEW MORE
story-3
Ford's 2001 Explorer Sportsman Concept Looks For a New Home

Slideshow: Ford's bizarre fishing-themed Explorer concept has resurfaced after spending decades largely forgotten.

By Verdad Gallardo | 2026-05-12 18:07:46


VIEW MORE
story-4
10 Best Ford Truck Engines We Miss the Most!

Slideshow: The 10 best Ford truck engines we miss the most.

By Joe Kucinski | 2026-05-12 13:09:47


VIEW MORE
story-5
2026 Shelby F-150 Off-Road: Better Than a Raptor R?

Slideshow: first look at the 810 hp 2026 Shelby F-150 Off-Road!

By Brett Foote | 2026-05-12 12:50:07


VIEW MORE
story-6
2027 Super Duty Carhartt Package First Look: 12 Things You NEED to Know!

Slideshow: Everything You Need to Know about the 2027 Super Duty Carhartt Package!

By Michael S. Palmer | 2026-05-07 17:51:06


VIEW MORE
story-7
10 Most Surprising 2026 Ford Truck Features!

Slideshow: 10 most surprising Ford truck options/features in 2026.

By Joe Kucinski | 2026-05-05 11:17:22


VIEW MORE
story-8
Top 10 Ford Trucks Coming to Mecum Indy 2026

Slideshow: Here are the top 10 Fords coming to Mecum Indy 2026.

By Brett Foote | 2026-05-04 13:49:49


VIEW MORE
story-9
5 Best / 5 Worst Ford Truck Wheels of All Time

Slideshow: The 5 best and 5 worst Ford truck wheels of all time

By Joe Kucinski | 2026-04-29 16:49:01


VIEW MORE