On removing the bottom fixings I was dissappointed to see the upper screw thread going into the adjustment sleeve is only about 10/12mm and with a very coarse (weak?) thread. The bottom thread is a very reassuring 25mm or so!
As this furling system is original and 43 years old now I wonder if there have been instances of the fitting failing as it looks to be a weak area. I quite like the downhaul halyard being self contained as I do not have a spare halyard for this as I have an extra large genoa on a bowsprit as an althernative to a cruising chute. I use the standard jib sheeted on the coachroof on the wind and the big genoa off the wind and light airs sailing.
If there have been any reports of Colnebrook failures I will need to think about it otherwise just carry on.