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AussieAub
11th January 2013, 09:47 PM
I HAVE searched, honesty, and come up with nothing!

Yesterday and last night I pulled out the fuel pump. Put it back in tonight, and with all the sound proofing out of the boot, realised that the strange noise I was hearing was actually NOT coming from the pump at all, but from the relief valve located tucked up behind the rear drivers side quarter panel.

Has anyone any experience of these valves in terms of noise and replacement/repair?
When under load, throttle down, there is no noise (or very little), but when sat idling, it develops a strange whirring/buzzing type noise which disappears when under load again. It is most definitely NOT coming from the pump.

I now believe THIS to be the culprit of my sudden stopping on the side of the road over the Xmas period, and not actually the fuel pump as first suspected.

Any help/advice greatly appreciated (as always!).

Cheers,

Trippy
14th January 2013, 11:16 AM
I suspect that I have this exact problem. I get a noise that when I first heard it sounded like someone honking their horn behind me. It only appears at low revs and disappears when I go faster. I assumed that it was a failing fuel pump but then I realised that the previous owner replaced the pump last year. So it would be very unlikely that the pump is failing again so soon.

Always when I open the fuel tank lid there is a lot of negative pressure, so this got me thinking there might be a release valve somewhere that is not working properly. I cannot find anything in RAVE mentioning a fuel release valve.

My car is a 1999 D2 V8.

disco2_dan
14th January 2013, 12:24 PM
Can't say I've had this issue.....yet, but going to keep an eye on this thread so if I do get it I know what to do, the only odd noise I get from the back every now and then is to me what sounds like a ****ed off rattle snake shaking its rattle for 1-2 secs then stops, can't work out what it is or why it does it?? It just randomly happens every second or third day? Lol

AussieAub
14th January 2013, 12:35 PM
I cannot find anything in RAVE mentioning a fuel release valve

The noise is most definitely coming from item 2 (Relief valve) on the linked diagram from the on-line RAVE resource.

Land Rover Workshop Manuals - Discovery II - Fuel tank and breather components (all except NAS) (http://landrover.workshop-manuals.com/discovery-ii/index.php?id=474)

Though it looks like a bugger to have to replace!

The pipe (3) physically vibrates when the noise is there. As my rear quarter panel is bent from a rock collision, I also noticed the relief valve (2) was vibrating against the bodywork, amplifying the noise. I nylon strapped it back to the fuel pipe (19) and made sure it was clear of the body. When it makes the noise, the valve also has a nasty vibration to it.

Is it supposed to? Or is it a sign of something else wrong. Cant see how it could be much as the assembly only runs from the tank to the filler hose.