Fuel tank outlet leak

[Marty V8]

Hi all,

I would be grateful if someone could help me with a problem I am having with the fuel tank outlet.

I have noticed a pong of petrol in the boot of my Griff since I bought it in July last year. I thought it was something to do with the petrol cap being under the cover of the boot lid, but when I investigated last week I discovered that the outlet from the tank was leaking.

The outlet uses a banjo coupling and after I took the tank out and had a look it seemed that the thread from the hollow bolt was bottoming out, as in, not letting the bolt tighten enough.

I fitted another copper washer so that there were two on one side of the banjo and one on the other, just so that the bolt would tighten fully.

I thought I had sorted the problem, but its still leaking. I have tightened the bolt over the past couple of days to the point that I'm now starting to get a bit twitchy about hauling on it any further - its a hollow bolt and I really, really dont want to neck it off. The leak has slowed but is still weeping.

Anyone had any experience with this and knows a good solution?

Cheers

Marty

[yellowgriff]

use plumbers tape (boss white,) its great for stopping leaks,,,

[roysum]

yellowgriff said:

use plumbers tape (boss white,) its great for stopping leaks,,,

Do you mean PTFE tape ? boss white is normally used on olives etc or with hemp on iron fittings.

[Marty V8]

Thanks for the answers.

I had another play with it today - fitted another different set of copper washers. These seem to be keeping the petrol where it should be, but Ive got it on ramps with the boot rubber bung out to see it it weeps during the night. Fingers crossed.

Cheers

Marty

[wycoller]

Marty V8 said:

Thanks for the answers.

I had another play with it today - fitted another different set of copper washers. These seem to be keeping the petrol where it should be, but Ive got it on ramps with the boot rubber bung out to see it it weeps during the night. Fingers crossed.

Cheers

Marty

make sure copper washers are annealed and flat use some very fine emery lay on flat surface, also ensure head of banjo and seating of washers on tank not damaged or burred

[Mr MoJo]

I had exactly the same problem last year. In the end it wasn't the fuel outlet pipe by the rubber bung, but a tiny pin hole had been worn through the bottom of the tank by a rogue spiky bit of fibre glass underneath the tank. The fuel was running along the bottom of the tank and collecting around the outlet pipe making it appear as though that was where the leak was when inspected with the bung removed.
If you've still got fuel escaping tomorrow, I'd have a good look at the tank itself just to be on the safe side.

[Marty V8]

Update on topic.

I took the tank out again and had a good look at the banjo fitting. Either side of the outlet the 2 opposite mating faces seemed to come together slightly such that both faces werent flat. However there seemed to be no scratches or scores that could have weeped petrol.

I attacked it with wet n dry to try to take out the dip in both faces to make them flat across their surfaces so that they would have a better chance of sealing. I used new washers - the crush type that are normally used as sump plug washers. Then I re-assembled it all and used a little thread lock on both faces of each of the washers.

I also had to raise the seating position of the tank so that it sits higher in the boot as the outlet pipe from the tank to the fuel pump was resting on the bottom of the hole through the boot, and I was worried that this would put strain on the banjo fitting. Bizzare!

It seems to have sorted it and I have had no leak since yesterday (Monday) afternoon - 20hrs and counting.

Fingers crossed again.

Cheers

Marty