Right; possibly the most laughable question of the year but I'm becoming annoyed now. Could someone tell me what should happen with the O ring when I screw the filter housing back on. Should it still be visible or should it disappear completely as I tighten it all back up again?
I have a feeling that (yet again) I have been supplied with an O ring which is too great a diameter so it doesn't quite fit. The resultant oil leak is starting to annoy me.
Simple question which should receive a simple answer.

it should still be a little visible but no more than 1-2mm as it should be thick  FFRR MY06 facelift With TDV8 Alloys Zeros/ATR's
Mantec Sump Guard, Rigid Load liner, MY10 BT upgrade.

Thanks for advice - I was being a bit thick. All sorted now

did you order the oil filter O-ring on its own, or with the filter? l=Oo\________/oO=l l:OolΞΞΞΞΞΞΞloO:l

Current
RANGE ROVER Vogue 4.4L SDV8 - 2013 - Indus Silver, on Almond.
RANGE ROVER Vogue 4.4L V8 - 2002 - ex-2003 G4 Challenge Event Vehicle, Stage 3: Australia
RANGE ROVER HSE 4.4L V8 - 2004 - one-of-one Overfinch
RANGE ROVER P38a 4.0L V8 - 1999 - ex-2000 TReK Event Vehicle: South Africa

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RANGE ROVER Vogue 4.4L TDV8 - 2012 - RANGE ROVER 3.6L TDV8 x3 - RANGE ROVER Td6 x1 - RANGE ROVER Classic 3.5L V8 x1

The large o ring comes with the new filter. I had just been a bit thick and not removed the old one from the cap, therefore there were two on at once, hence my problem.