Oil pressure build up

[Spider2]

I changed my oil filter recently and ever since the oil pressure has taken a long time to build up on engine start (8-9 seconds). It is as if the filter keeps draining after the engine is switched off. Apparantly there is an anti drain valve in the filter housing but I cannot work out where it is from the parts diagram. Any clues?

[lancialulu]

It relies on the anti drain flap in the filter and the long tube in the housing. A lot of compatible filters are only compatible in size and thread..... What filter did you fit?

[Spider2]

I copied the number from the old filter which had no problem: Bosch P 4063. Long number 0 451 104 063.
I have to admit I bought 2 off e-bay for an amazingly good price. I now notice that they were made in Poland. I suspect you are correct about it being compatable in size and thread only. Teach me for trying to be economical.
Who sells 100% correct ones and what should I be looking for on the box? Also what part number is recommended?

[Spider2]

Thanks Tim, you were spot on in your diagnosis of my very slow oil pressure buildup.  I replaced the filter like for like a few months ago (Bosch P4063). The first one came as a spare with the car when I bought it and worked fine. I bought a replacement on ebay and this is the one that caused the problem.
I have just replaced the filter with a Flamm FT4403 bought from a very reputable supplier and the oil pressure build up is now almost instantaneous.
I guess the lesson for all of us is stay away from cheap ebay spares.