Fuel leak advice

[Vinny]

Hi Everyone,
Drove the Z out of the garge yesterday - when I got out - car on the drive - there was a strong smell of petrol and a dark patch on the drive.

Took a look underneath and I could see petrol dripping from off the tank onto the exhaust below.

Jacked the car up to get a better view and turned the ignition on - immediately fuel started leaking again - clearly a leak from a pipe somewhere above the tank or certainly out of sight - stops immediately there is no longer power to the pump.

Located the cover over the pump and removed it - no sign of any leak there all looks in good condition.

So I am guessing its a failure in the fuel line flow / return don't know which.

Only way to see whats going on is the drop the tank which looks like a lot of work - I assume prop & diff have to come off.

Unless you guys can tell me different - is there a way of removing the fuel lines without disturbing the tank? - long shot and probably wishful thinking

Car cannot be driven the leak is just too severe and dripping on to the exhaust - not something I think I can repair on my drive - don't have ramps etc

Local decent garage charges £102 / hour inc vat labour - ouch 3 weeks before they can look at it

 

[IainP]

You can access them, but they clip into the top of the tank and you can’t access those without dropping the tank.
I replaced mine with kunifer because the condition of the metal ferrules scared the life out of me. New originals are available, over £200 I think, the kunifer I already had.
Fuel pressure is generally around 2-3 bar on most cars, more than enough to create a big problem quickly.
Where are you located, someone local may be able to give you a hand.

 

[Vinny]

Brill info thanks Iain
The pictures really help
What I don't understand is why the is suddenly a leak in the pipe
A corroded joint I would get but I think there must be a whole in a pipe

I live near Bridgnorth in Shropshire

 

[IainP]

Or a split , they hold until they don’t. I’ve put out enough Motorsport fires, it does usually happen suddenly.

Unfortunately, nowhere near me, I’m in deepest Scotland.

Possible option would be 8mm bore braided stainless hose with Magna clips ( jubilee/worm type clamps specifically for braided). Feeding it up over the tank might be a challenge. Some bendy wire maybe? Cheap fix though, it’s around £12 a meter. I’d go stainless over fabric braided since it would be sitting loose.

If in a garage, keep it well ventilated, liquid petrol isn’t flammable in itself, it’s the vapour that has the low flashpoint, also pretty toxic too.
If you have a powder extinguisher keep it handy, better than foam, or co2.

 

[Vinny]

Meant to ask.
What has to be moved to allow the tank to come out?

 

[IainP]

Lots unfortunately , rear exhaust, prop disconnected, full rear beam.

 

[Vinny]

Finally managed to get the car onto a lift so able to get decent access and light on the job.
Seems I am lucky yet unlucky.
Found a tiny hole in the line where the flexible connects to the plastic
I reckon it had been chewed by a mouse

 

[TriumphZ3]

Well now you know, so that's something, and it gives you something definite to address rather than the unknown.
I had pipes failed in a Discovery TD5, left a lovely rainbow pattern on a wet road for about ten miles and nothing for it but tank removal and pipe replacement. Good luck with the repairs, it may seem like a lot of work but it all flies together in the end.

 

[Andyboy]

I would replace them all with proper BMW rubber fuel hose. With the tank in you can feed it through the pump access hole up and down again but it’s bloody fiddly. I bought a pair of four metre lengths, enough to do both with some left over. It’s much easier with the tank straps cut off so the tank can be moved about a bit. I bought a pair of secondhand E46 straps, cut them and shaped them to match the rotten old Z3 straps, using dome headed coach bolts and nyloc nuts to clamp the two halves. Someone here makes/made new straps that can be fitted without taking half the car apart.
Washing up liquid makes the fuel hoses slide in easier.

 

[Vinny]

New tank strap fitted supplied from here