Quote: (Originally Posted by
hrdubwd)

That would be bizarre, but the probability is not zero. Much more likely is that it is damaged. Not knowing that an O-ring is there might mean that it has not been looked after.
I have had a very senior instructor swear blind that there is no O-ring in a direct feed hose connector ... and wonder why it leaked. You are not alone.
BWD
Missing would manifest is self as leaking the first hour in the water .... so I agree with you damaged is more like it.
but it does not change the fact that I don't see it..... is it recessed?