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Fuel Leak Above Pass. Side Rear Tire

  • Thread starter Thread starter atey950
  • Start date Start date Nov 5, 2012

atey950

Founding Member
Aug 5, 1999
516
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59
Southeastern PA
Nov 5, 2012
#1
  • Nov 5, 2012
  • #1
Car has sat for about a year and went to start it yesterday. I noticed strong fuel odor so I shut it off and walked around and found that gas had leaked from above the pass. side rear tire. I didn't remove the tire yet to get a good look but does anyone know what this could be?

Surely a rotted or rusted line that needs to be replaced. Hoping I can access it by removing the tire and not have to drop the tank. I'm assuming it's a return line because the car did start and idle for a short time before I turned it off.
 

Noobz347

Stangnet Facilities Maint Tech... Er... Janitor
Admin Dude
Jan 4, 1985
43,114
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Box behind Walmart
Nov 5, 2012
#2
  • Nov 5, 2012
  • #2
Probably a rotted donut seal around the fuel fill line, into the tank.
 

Onefine88

Previously 89SSC18
10 Year Member
Aug 3, 2006
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Nov 5, 2012
#3
  • Nov 5, 2012
  • #3
If its dripping on the floor only when the key is on, it is probably one of the fuel lines. Be careful, the fuel lines and the exhaust are in very close proximity right behind the axle. Very dangerous place to have a fuel leak.

My lines and exhaust got together right there while I was on a road course racing my SSC about 5 years ago. Burnt a hole in both lines. Luckily one of the track safety workers saw gas pouring from my car when I passed and I was black flagged.
I was lucky it didnt catch fire.
 

88LX5.Oh

15 Year Member
Dec 30, 2011
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Nov 6, 2012
#4
  • Nov 6, 2012
  • #4
My return line was rotted out when I bought my car. But the donut seal is definitely the first thing to look at. If you find yourself replacing the seal, lube the new seal up so the filler neck won't mess up the new seal. I used white lithium grease.
 

atey950

Founding Member
Aug 5, 1999
516
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59
Southeastern PA
Nov 6, 2012
#5
  • Nov 6, 2012
  • #5
Thanks for the replies. Do all of these require dropping the tank?
 

88LX5.Oh

15 Year Member
Dec 30, 2011
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Nov 6, 2012
#6
  • Nov 6, 2012
  • #6
atey950 said:
Thanks for the replies. Do all of these require dropping the tank?
Click to expand...

Replacing the return line does, but the donut ring doesn't. I think I recall someone on here recently replacing the donut ring without dropping the tank.
 

atey950

Founding Member
Aug 5, 1999
516
60
59
Southeastern PA
Nov 16, 2012
#7
  • Nov 16, 2012
  • #7
88LX5.Oh said:
My return line was rotted out when I bought my car. But the donut seal is definitely the first thing to look at. If you find yourself replacing the seal, lube the new seal up so the filler neck won't mess up the new seal. I used white lithium grease.
Click to expand...
would the donut seal cause gas to leak when idling?
 

srtthis

the guy doing it does every local racers rear end
15 Year Member
Jul 3, 2009
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Maryland
Nov 16, 2012
#8
  • Nov 16, 2012
  • #8
atey950 said:
would the donut seal cause gas to leak when idling?
Click to expand...
depends on the fuel level
 

atey950

Founding Member
Aug 5, 1999
516
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59
Southeastern PA
Nov 16, 2012
#9
  • Nov 16, 2012
  • #9
srtthis said:
depends on the fuel level
Click to expand...
half tank
 

srtthis

the guy doing it does every local racers rear end
15 Year Member
Jul 3, 2009
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Nov 16, 2012
#10
  • Nov 16, 2012
  • #10
hard to say since the gauge in a fox works about as well as a guy on unemployment... if its above the seal yes it will leak.. if its below the seal it will only leak when your going around a left hand turn
 

bdep73

Member
Jan 15, 2012
31
1
8
hartford, CT
Nov 16, 2012
#11
  • Nov 16, 2012
  • #11
I am almost 100% certain you have to drop your tank to replace the donut seal because the seal goes around the filler neck base which is a good 8 inches in the tank. I had to drop my tank this summer to put in a larger fuel pump and I had to lower the tank before I could get the filler neck out if the tank and it was a pain in the ass getting it out. You don't have to drop the tank completely but you definitely have to undo the straps to get the neck out to replace the donut
 

f8tlfiveo

My wife likes my spool and blow-off valve.
Aug 8, 2007
1,585
102
64
Lancaster, PA
Nov 16, 2012
#12
  • Nov 16, 2012
  • #12
88LX5.Oh said:
Replacing the return line does, but the donut ring doesn't. I think I recall someone on here recently replacing the donut ring without dropping the tank.
Click to expand...
I just did the seal without dropping the tank..
 

f8tlfiveo

My wife likes my spool and blow-off valve.
Aug 8, 2007
1,585
102
64
Lancaster, PA
Nov 16, 2012
#13
  • Nov 16, 2012
  • #13
bdep73 said:
I am almost 100% certain you have to drop your tank to replace the donut seal because the seal goes around the filler neck base which is a good 8 inches in the tank. I had to drop my tank this summer to put in a larger fuel pump and I had to lower the tank before I could get the filler neck out if the tank and it was a pain in the ass getting it out. You don't have to drop the tank completely but you definitely have to undo the straps to get the neck out to replace the donut
Click to expand...
Nope.. It can be done with tank not touched.. Take the wheel off for better access.. Take the bolts out of the top at the gas door, the seal on the bottom and the brace on the tank.. Takes a little wiggling but much easier than dropping tank
 

88LX5.Oh

15 Year Member
Dec 30, 2011
1,442
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94
Arkansas
Nov 16, 2012
#14
  • Nov 16, 2012
  • #14
f8tlfiveo said:
I just did the seal without dropping the tank..
Click to expand...
Did you make a thread about it? It might have been you who I was thinking of
 

f8tlfiveo

My wife likes my spool and blow-off valve.
Aug 8, 2007
1,585
102
64
Lancaster, PA
Nov 17, 2012
#15
  • Nov 17, 2012
  • #15
Sort of.. I asked the question if anyone has ever done it.. Then after I did it I think I posted the process I took.
 
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