Leaking Fuel Filter

[junglieD]

Edited to say - *Leaking Fuel PUMP*!!!

Hi All,

I've just got back from a great run-out in the Cotswolds and having washed, dried and put the car away in the garage I noticed a bit of a fuel smell which I traced to a drip/leak inboard and forward of the rear nearside wheel. I have to admit - I've seen a small leak in the past there and put it down to soapy water following a wash but seeing as I had plenty of daylight left I confirmed that it was fuel - not water - and that it seems to be coming from the fuel pump. Unfamiliar with the part I reached for the bible and initially could see that my Clamp Securing Bolt is missing from the metal clamp meant to hold the pump in place:

• What length and size of nut/bolt is required for the clamp? (component D in the top diagram)

The fuel is pooling at the head of the fuel outlet (A in the top diagram) before it drips to the floor. You can see the beginnings of a drop of fuel in the photo of my fuel pump below.



Like I said, unfamiliar with the part I read through the bible and thought an extra turn of the fuel outlet head might tighten it and stop the drip.... no joy - it has exacerbated the problem and the slow drip became a faster drip and then when I turned it the other way caused a hiss as air pressure/fuel pressure escaped. After the panicked loosening and tightening of the fuel inlet to stem the flow I've reached a happy medium of about the same leak rate as before I touched it - 1 drip every 1.5 secs.

• Can anyone clarify - is my logic correct that tightening the fuel outlet should tighten the seal and thus prevent a leak?

Because my pump is not as secure as it should be - missing clamp bolt - I cannot get much of a turn in either direction before the whole unit moves with the force. I used another spanner to grip the brighter coloured metal further inboard from where the main fuel outlet 'head' is but this is when the fuel leak got significantly worse so I loosened it back to the 'happy medium'.

I have now disconnected the bottom wire and am venting my garage. I'll check on it before bed and disconnect the battery too so as to remove any chance of sparks. Fortunately my fuel level is v.low so if the worst happened I could only have what's in the pipes + about 2 or 3 litres drain on the floor.

• Has anyone had a similar fault before or have any guidance for rectification? Search function is still down obv.

As a bit of background. The previous owner installed a new fuel pump in June 2011. It has only done about 1000 miles since then. Thanks in advance,

David

Edited by junglieD on Sunday 26th February 18:35

[mep12345]

David,

Those are Banjo connections, basically the fuel comes up a drilling in the "bolt" bit (A in the diagram) and then enters a "doughnut" shape that the fuel pipe comes off of (between the yellowy washers in your picture). The sealing should be created by two copper washers either side of the banjo (doughnut shape), it looks like yours are some sort of plastic. If they are copper and just discoloured then I would think it likely that the copper washers were not replaced when the fuel pump was and hence they are overcompressed (in fact the top one looks damaged in your photo).

If I was you I would undo the banjo and drain what fuel is there into a container (this will just be what is in the line) and then do up loosely until you can get replacement copper washers then refit with the new washers and do not overtighten. Definately don't drive it until sorted though.

Mark

Edited by mep12345 on Sunday 26th February 20:06

[junglieD]

TVM Mark for your quick reply. I think I understand what you mean in describing the banjo connector. The drip has actually stopped now so it is likely that the bulk of the fuel in my pipes has drained out. I'll undo the banjo bolt and check the condition of the two washers as you suggest - I imagine the donut shape will become clearer in my mind when I see it undone anyway. It's nice to have clarification that my whole tank won't empty out when I undo the connection - even though my tank is low, that would not be much fun.

• Are the copper washers pretty standard - from my local motorfactor?
• If any part of my banjo turns out to be at fault rather than the washers - is it possible to purchase replacements?

Regards

David

[Elfit]

I agree with Mark.
The banjo is unlikely to be at fault ~ it's just a lump of metal. The washers will take up any irregularity.

Can't remember the size of the clamp securing bolt. I can confirm that it's a fiddly little bugger.

cheers

Tim

[mep12345]

It is unlikely the banjo is at fault here, but if it is damaged then you should be able to get a replacement from any autofactors but they'll need to match the size.

This pic will help with what a Banjo connector is



The fuel from the tank comes in through the larger bore pipe at the other end of the fuel pump via the surge valve (the right angle one that stops fuel pressure pulses - at least thats what I think it does) IIRC. I tried to but can't find a picture

Mark

[phillpot]

Beaten to it while I was re-sizing photo!



This isn't actually off an S but same principal, those copper washers are most likely your problem ( Alluminiun in Marks picture?)


I'd take a good guess at the clamp bolt being M8 (13mm spanner) x about 30mm long, and I'd go for a "Nylok" nut.

[junglieD]

Thanks for the pictures - I have a clear idea of what to expect now. I'll do what you have both said and remove the current washers, purchase some like-size replacements at my local auto shop and refit being careful not to over-tighten. I'll also purchase the 30mm bolt and Nylock Nut to properly secure the pump. I'll let you know how I get on but hopefully this could be the end of my leak.

Regards

David