Hi there
I decided to flush my gearbox and change filters, seal, etc as the sump has been leaking
The start was delicate as 3 of the screws where hidden by the non original exhaust. I found the solution in loosening the screws securing the exhaust to the chassis,

Then removal of the 20+ screws holding the sump ; in order to avoid a shower, I left the big bolt fastening the oil gauge(also because I read it was nearly impossible to unscrew )

Some prying was necessary to open the sump and ?have a shower ; hopefully I had placed a bucket below and stepped back !

To finish the flush , I used a watering hose as a siphon

Then I tried to remove the sump+gauge attached , but there was no way to remove it from underneath (nor top of course) . So there was no other way than unbolting the 1? (?) bolt ; managed o do it with aan adjustable spanner and a hammer (after resecuring the sump with 4 screws to prevent movement)

Sump removed and emptied : what was left inside ?
The bas news :
? 2 broken parts

? No magnet found
? Filter is a little damaged on side
The good news :
? Hardly any trace of metal grindings on filter or elsewhere

? Finally the bad news of the broken bit in Aluminium/Mazaks might not be serious ; it?s only contributing slightly (with 4 other screws ) to closing 2 halves of an enclosure ; there it goes; I could refit it and as it broke with a "T" shape, it stil plays some role in fastening the Mazak enclosure

? The 2nd broken part is only the missing magnet holder (pic taken after cleaning the sump !)

? The bottom of the sump contained no other debris , just dirty oil
Removal of the filter (simply clipped) and change with a new one : surprise the one provided by B?tt is different !
The filtering mesh is now on top instead of bottom ; let?s assume it?s an improvement of the function ?.?
When refitting , I was surprised that there is no real sealing between the filter and the pipe, I was expecting a rubber seal
Removal of the old cork seal , main reason of flunshing the box as it was leaking
Refitting of this pipe (which seems to lubricate the top of the box, and fell down when opening the sump); on top it doesn?t sem to enter any aperture
The new seal
The new magnet from my toolbox; just stuck to the sump; any need of securing it ?
Refitted the sump with 4 screws to protect box from any dust before next steps
What I believe as certain :
? The cork seal was leaky and faulty; needed definite replacement
? I could retrive all oil that I had introduced during previous flush with the pump, plus old one
My questioning :
? What happeed to the magnet ? forgotten by PO during previous flush ? destroyed ? (should be traces left somewhere in this case)
? I was expecting a clogged filter explaining low pressure when I previously partly flushed the box with pump ; not the case : i slow pressure normal ? could it be due to the returning pipe not well placed ?
? The edges of the sump are not exactly flat, and thickness is not sufficient (poor design explained elsewhere) ; I will consider having metal bars of says 3mm thickness cut on purpose , with longer screws, in order to have a much more even pressure on the seal
Any thoughts ?