First post after changing my 07GS for MY11GS. Everything OK BUT:
almost impossible to remove fuel cap when want to refuel. At one time I considered using mole-grips. When I did manage to get the cap off there was a big in-rush suggesting a big vacuum in the tank. Just did my third re-fuel with similar problems.
Have read previous posts (Yosser395 Jan2011) and the one from Alex with a link to cleaning the fuel cap. The vehicle has only done 7.5K so fuel cap looks spotless so don't think a clean is necessary.
Before going to dealer (vehicle under LR Used warranty) does any member have a feasible explanation of why this should occur (ie is there a breather pipe or is the fuel cap solely responsible for equalizing the tank pressure). 11 GS Bali Blue
07 GS FL2. Usually muddy. Gone
Numerous LRs since 1963

I've not found the cap difficult to remove but am also getting the sound of air rushing in on my newly acquired MY2011 SD4....never had this with my previous MY2007 XS.

Is this a problem or normal? The design of the filler is different because of the misfuelling device now fitted - could this be why? 2011 SD4 HSE Auto
(Previously 2007 TD4 XS Manual)

Would putting a small hole in the cap help relieve the pressure Ex 2010 Freelander2 GS-e Diesel manual Silver owner

I've previously posted the same observation.
I went from a 2007 vehicle to my present 60 plater, and found it very difficult to remove the cap the first time. It seems to be though that you only need a small anti clockwise twist, and then just pull it off. I also get the mahoosive rush of air, but it all seems to work as it should.

It's worth getting this checked out, as a vacuum developing in the tank will place extra stress on the fuel pump and could ultimately lead to fuel starvation.

The tank does have a breather mechanism, so it sounds as though something is wrong/blocked in that mechanism. This from an 09-ish manual:

Quote:

Fuel Tank Breather Valve

The breather valve is located in the fuel tank and is connected to the fuel delivery module flange via an internal breather hose. The breather valve allows air to escape and enter the fuel tank to compensate for the changing volume within the tank.

...

A breather hose is routed from the fuel filler pipe to the fuel delivery module flange. The breather hose connects to the breather pipe on the fuel delivery module flange.

Just a thought....could it be different because of changed emissions regulations...fuel vapours? 2011 SD4 HSE Auto
(Previously 2007 TD4 XS Manual)

I don't know whether there's been a change in the latest cars or not, but AIUI there should still be a venting mechanism and it's more where rather than whether the pressure is released - e.g. I believe US regulations require venting into the engine intake so that any vapours are burned in the engine. Also, I don't know whether the same regs apply to diesel as to petrol, the former being rather less volatile. But in any case, a pressure difference in the tank such that the filler cap can't easily be removed doesn't sound normal.

I'm the instigator of this thread so here's the latest:

With my previous 07 FL2 I used to just screw up the filler cap through numerous 'clicks' and there was no difficulty in removing. With my MY11 vehicle I have learnt to just screw the filler cap past 1 'click', this makes it a lot easier to unscrew and with less of a hiss when removing. Still unsure on whether there should be a vacuum when removed, next time I'm in Exeter I'll pop in and consult the LR dealer "experts", (but don't hold your breath for a technical explanation) 11 GS Bali Blue
07 GS FL2. Usually muddy. Gone
Numerous LRs since 1963

Mine's going in Monday for them to have a look.....will update when I've got something?! 2011 SD4 HSE Auto
(Previously 2007 TD4 XS Manual)

768will wrote:

Still unsure on whether there should be a vacuum when removed, next time I'm in Exeter I'll pop in and consult the LR dealer "experts", (but don't hold your breath for a technical explanation)

Update.....car's been to dealer this morning and they agree it's abnormal. They've ordered a replacement filler cap - their diagnosis is that valve in cap isn't working properly. 2011 SD4 HSE Auto
(Previously 2007 TD4 XS Manual)

Update continued......new filler cap has solved the problem so presumably the valve in the old one had malfunctioned. 2011 SD4 HSE Auto
(Previously 2007 TD4 XS Manual)

Probably you would have saved some quids if you've followed the procedures here:
http://www.freel2.com/forum/post218203.html#218203

Thanks Alex.....but cost me nothing - they simply replaced it! 2011 SD4 HSE Auto
(Previously 2007 TD4 XS Manual)

This could explain one reason for chugging at low revs as if the pump is pulling against the vacuum. Mine does the same as far as inrush is concerned. Will clean at the weekend. Had it before on another car. Drives better with a full tank as less room for vacuum.