M50 Cylinder Head Non Return Valve

[93 525 Paul]

Dont think it needs to hold 3 bar - I think the idea is it just stops oil from draining back down? IIRC they unscrew if you want to replace them. I just made sure mine wasnt stuck

Mine seems fine, clean as a whistle and works, can see the ball and spring check valve. Holds a bit, it's a very light spring.
Thanks! No excuses, mount that sucker up...

[93 525 Paul]

Here's what it looks like, came out easily back when I was cleaning the head up, lapping valves etc.


Here it's being reinstalled in the head