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mrapocalypse
18th May 2009, 05:15 PM
There is a famous audible humm in D2 V8s, which in mine is a vacuum in the fuel tank. When it humms, if you open the fuel cap it'll suck a whole lot of air, like a deep inhalation of breath! Is this bad?

It can't be good for the fuel pump to be sucking against that heavy vacuum, shouldn't the breathers be letting air into the tank? It has Long Range tanks and I have a heavy foot! Maybe i am using more fuel than the engineers had in mind....

At least I know my LR tank rep[airs are air and fuel tight!!!

harry
18th May 2009, 05:59 PM
that's the way it's s'posed to be.
although, i think it is pressure, not vacuum
although the humm may be an indication of a crook valve in the fuel cap

Blknight.aus
18th May 2009, 06:49 PM
thats normal.

try it again when youve just filled up the tank.

You'll find that the vac isnt all that great in terms of pressure differential but when you have70l worth of tank at that low pressure it takes a fair bit of air to refil it. open the cap and all that air goes in. when the tanks nearer to full it takes less air to bring the tank back to normal pressure so less air rushes in.

mrapocalypse
19th May 2009, 10:11 AM
Seems a bit odd tto me. So what's with all the breathers and stuff? Why have em if the tank is airtight?

Pedro_The_Swift
20th May 2009, 05:30 PM
mine hums on occasion,,,

LandyAndy
20th May 2009, 10:16 PM
HUMM IM EMPTY AGAIN:p:p:p:p
TD5s dont suffer from this ailment:p:p:p:p:p
Andrew

mrapocalypse
21st May 2009, 12:26 PM
It's true Andy, it humms loudest when I've been THRASHING it. :D:D:D

I can't help it. I'm sorry planet Earth!

Lousy sports exhaust!

:wasntme: