I dont have any images but I will attempt to describe whats in there to you, once the sphere is removed looking into the hole you will see a bolt (8mm) this holds a small plate behind which lives the ball bearing, remove the bolt and plate and the BB should just be visible, I made a brass punch up using a small rawlpunch, rubber tubing and an old Mig welder tip (brass) and was able to seat the BB without any further dismantling with the front of the car on ramps.
Stewart
BXs since 1993 built 1.9 TZD turbo, got a S2 Xantia estate, brilliant car! 2013, Xantia HDI LX 110 2000 new car with 122,000, l C2 HDI Rusty rocket, C3 Picasso HDI new to me.
It is worth taking the BB out and checking the seating for bits of crud trapped there, it does not need to be hit hard with the punch or you could make it even worse, I believe the BB is a standard size if its not round.
Stewart
BXs since 1993 built 1.9 TZD turbo, got a S2 Xantia estate, brilliant car! 2013, Xantia HDI LX 110 2000 new car with 122,000, l C2 HDI Rusty rocket, C3 Picasso HDI new to me.
Its not because the bb has moved, but because the bb & seat have had endless contacts since '93 and therefore the seat surface *may* no longer be leakproof.
The idea is based on the assumption the bb is made of harder steel than the seat, and therefore will make a perfect sealing ring mark when the bb is hit hard against the seat.
Even the smallest imperfection or grain will make the bb valve leak. It may even suffice to clean it well using a cotton stick. But while you are there to do exactly that, why not ... etc etc.
I tried it because I had 2 regulators that cycled quickly with a new accumulator sphere. On looking at diagrams it seemed that this ball was a likely candidate - and I'd used the technique when overhauling a Laycock overdrive many years ago - where it was so successful the thing wouldn't drop out - but that's another story.
Ball bearing is a standard metric size - shown in exploded diagrams of the regulator but it is a different size to the one under the pressure relief bolt.
I rather think as this is in fact the inlet to the accumulator that anu dirt would have been carried away in the flow - but its worth a look.
The seat is simply a hole drilled in the casting - and tapping the ball home just smooths out the imperfections that as Anders says, have developed over the last 13 years.
Good bit of engineering if all it needs after 13 years is a ball bearing valve re-seating!