|
|
|
|
|
#1
09-23-2011, 10:26 PM
|
|||
|
|||
|
Leaking gas line - forever
Fuel pump went out.
94 SL320 Replaced it - leaking. Put two silver washers which came with the new fuel pump. Still leaking. Put two brass washers still leaking Put two washers used for battery terminals half encased with rubber. Six months later leaking again. Tightening leaking spot - the fuel pump tears open. New fuel pump. Mechanic suggests two rubber O-rings. When tightened they begin to bow out. (See photo) I know this will leak as there is a clear way for it to escape via the bowed out ring. Leaving bolt loose so they dont bow leaves me to believe vibration will easily loosen the bolt to falling off. Gallery of photos of fuel line Im speaking of. Fuel pump closest is culprit. O' rings are the black lines. ImageShack Album - 8 images What washers should be used on a metal on metal fuel line? And where to get them? Last edited by Mal; 09-23-2011 at 10:27 PM. Reason: Ensure email notification enabled. 
|
|
#2
09-24-2011, 02:43 AM
|
|||
|
|||
|
I changed the fuel pump on a w126 (it looks close enough to what is in your pic that i believe it applies to this situation) and it just had brass washers in it. Did you use an OEM fuel pump? If it leaked with brass washers where you have the o-rings, it sounds like either the threads on the fuel pump or the line are damaged or not made quite right. If it was my car my next step would be to try a known good used fuel pump and replace the part of the line which threads into the leaking connection as well with a used one.
|
|
#3
09-24-2011, 10:13 AM
|
|||
|
|||
|
I recently had to change my fuel filter and the copper crush washers supplied with the new unit (Bosch) weren't the same size as the originals; not even close. I went to the dealer and got the correct size by matching to the old washers. ( They charged 75 cents each ). This is a case where I believe that the thickness is as important as the I.D. and O.D. size of the washer. I don't think a rubber "O" ring is suitable and teflon tape is not recommended on fuel lines, but you might find and try a fiber washer from the plumbing section at the hardware store to use in addition to the crush washer ( where you have the o-ring now).
__________________
Resistance is Futile.
|
|
#4
09-24-2011, 11:48 AM
|
||||
|
||||
|
The check valve uses three flat copper washers. 1 thick where the valve screws into the fuel pump. Two thinner. The thinner ones go on either side of the banjo fitting. The cap nut tightens the banjo fitting to the check valve.
Check the inner and outer surfaces of the banjo fitting for damage. You might also try switching the fuel pumps. The silver washers were defininltly wrong for this purpose. (BTW, The 107 560SL has the same setup with the same fuel pumps etc.)
|
|
#5
09-25-2011, 03:38 AM
|
||||
|
||||
|
Quote:
 You need copper washers - not rubber -not silver - not steel JUST COPPER BUT The trouble with banjo connector copper washers is that they "harden" when they have been used, even if it's only once, however Copper washers are what you definitely need to use and the best way is to clean and anneal the old ( original) copper washers if you still have them.(Even if the instructions say you MUST use new ones - finding the correct size in new copper washers is like finding hens teeth  )(Annealing or re-softening metal removes the "work hardening" from the surface of the copper allowing it to mould when tightened and make a prefect seal with the "banjo" connector) Method:
edit: I just spotted a You-tube vid on annealing- Copper Annealing - YouTube Might be useful THEN when you re-use the newly softened washers DO NOT ADD ANY RUBBER WASHERS, SEALING COMPOUND OR ANYTHING ELSE - just Metal to Metal, a copper washer each side of to the brass (normally) banjo and you will get a perfect seal on the surfaces of the banjo connector AND NO MORE LEAKS  Cheers Jim
__________________
Keep your Motor runnin'  Jim's '88 300SL
Last edited by coleyjf; 09-26-2011 at 08:48 AM.
|
 |
| Bookmarks |
|
|
Linear Mode
