Oil pressure switch leak

[MarkBos]

Hi,
I have an oil leak from the blue low pressure switch in between push rods (1.9 DG petrol)

I ordered a new one from brickwerks OPS01, but it doesn't fit (diameter too large I think), has anyone had this problem before?

To my eyes they look very similar in diameter, thread and length, although the new one is tapered at the beginning of the thread (old one flat)

I've tried cleaning out the hole, incase there was any dirt etc, but still no luck. Any thoughts?

Thanks,
Mark

[Aidan]

maybe the wrong switch, should be 10mm parallel fine thread 1mm pitch, shouldn't have a taper, maybe a rogue 3/8 " npt switch got in the batch and wasn't spotted