Results 1 to 9 of 9

Thread: Fuel leak under fuel tank

  1. #1
    Join Date
    Apr 2012
    Location
    SPAIN
    Posts
    162
    My Cars
    NISSAN

    Fuel leak under fuel tank

    Fuel leak under the fuel tank, probably a hose, although I still don't know where it comes from. How do you change these hoses?

    It's probably one of these.

  2. #2
    Join Date
    Aug 2009
    Location
    sunnyvale CA
    Posts
    1,592
    My Cars
    325is
    the top of the tank has 2 ports that are under the rear seats. Need to remove the cover hatch too to access. The tops are plastic and the hose bib connection cracks so it may not be hose problems.

  3. #3
    Join Date
    Apr 2012
    Location
    SPAIN
    Posts
    162
    My Cars
    NISSAN
    Quote Originally Posted by gc325is View Post
    the top of the tank has 2 ports that are under the rear seats. Need to remove the cover hatch too to access. The tops are plastic and the hose bib connection cracks so it may not be hose problems.
    Okay . The strange thing is that when it started it doesn't lose any fuel, it's when about 2 minutes pass when it starts to lose and it's a lot I have to stop the engine because it leaves a puddle. I have to check as you say from under the seats to see if I see the problem.

  4. #4
    Join Date
    Apr 2012
    Location
    SPAIN
    Posts
    162
    My Cars
    NISSAN
    This morning I started the engine again and I didn't lose anything in the tank area yet but then it started to lose due to a hose in the engine area I tightened the flange a little more and I had it for about 20 minutes and nothing at all no longer lose The car was stopped for 1 year, could this be the cause?

  5. #5
    Join Date
    Aug 2009
    Location
    sunnyvale CA
    Posts
    1,592
    My Cars
    325is
    Gas is sent from the tank to the injectors ~ 45 psig. Excess unused fuel is returned to the tank. When the car is stopped, the excess fuel/ pressure will slowly be sent back to the tank. Sound like a return line or hose could be a problem and maybe just a clamp. Leaks can also happen at the fuel filter area. Note the top of the tank has a recessed cap and can hold a cup of liquid. A slow leak can take some time before yo see it drip.




    Last edited by gc325is; 07-29-2023 at 01:54 PM.

  6. #6
    Join Date
    Apr 2012
    Location
    SPAIN
    Posts
    162
    My Cars
    NISSAN
    Quote Originally Posted by gc325is View Post
    Gas is sent from the tank to the injectors ~ 45 psig. Excess unused fuel is returned to the tank. When the car is stopped, the excess fuel/ pressure will slowly be sent back to the tank. Sound like a return line or hose could be a problem and maybe just a clamp. Leaks can also happen at the fuel filter area. Note the top of the tank has a recessed cap and can hold a cup of liquid. A slow leak can take some time before yo see it drip.




    Yes, I removed rear seats and metal cover and it was just a little damp. It didn't lose there either when it was on. I lost a lot the first day of starting and now nothing. Maybe the hoses were very dry, but I don't know.

  7. #7
    Join Date
    Jun 2009
    Location
    PAC
    Posts
    452
    My Cars
    '95 E36 M3
    So it was leaking at the tank first then at the engine?
    I recommend you replace the fuel lines at the tank and engine just to be certain they won't fail as you start to drive the car more.

  8. #8
    Join Date
    Apr 2012
    Location
    SPAIN
    Posts
    162
    My Cars
    NISSAN
    Quote Originally Posted by Veleno View Post
    So it was leaking at the tank first then at the engine?
    I recommend you replace the fuel lines at the tank and engine just to be certain they won't fail as you start to drive the car more.
    If that is . At the first start, it dripped a lot in the tank part. The next day it was already good and it was the engine area and for I now nothing is leaking. The car was stopped for 1 year, maybe the pipes were dry. When I can I will replace them but they are in a somewhat difficult area to access.
    Last edited by boeing747; 07-30-2023 at 10:16 AM.

  9. #9
    Join Date
    Aug 2009
    Location
    sunnyvale CA
    Posts
    1,592
    My Cars
    325is
    Google must have read some of the replies and sent this video on how to fix up a E36 <a href="http://www.youtube.com/watch?v=lE4M1uTHMSg" target="_blank" rel="nofollow">www.youtube.com/watch?v=lE4M1uTHMSg</a> if you get to 49 min you can see what the gas lines look like and how to replace in the car. Not sure where he got the new belt tensioner but he is not in the US.
    Last edited by gc325is; 08-26-2023 at 08:16 PM.

Similar Threads

  1. Help please, Fuel leak from gas tank area when running.
    By kawgpz750 in forum 1983 - 1991 (E30)
    Replies: 2
    Last Post: 05-17-2013, 02:14 PM
  2. Replies: 6
    Last Post: 11-05-2010, 10:29 AM
  3. Fuel leak under Intake manifold, help me please!
    By R.R in forum 1991 - 1999 (E36)
    Replies: 4
    Last Post: 03-27-2008, 09:15 AM
  4. fuel leak from above tank?
    By izzy325is in forum Forced Induction
    Replies: 9
    Last Post: 03-10-2008, 07:24 PM
  5. fuel leak by gas tank
    By 410225 in forum 1991 - 1999 (E36)
    Replies: 0
    Last Post: 09-17-2005, 07:32 PM

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •