Barlow 32 self tailing winches or not

[geem]

My elderley Barlow 32 self tailing winches don't self tail. The jaw is not sprung but fixed. Anybody know what size and type of genoa sheet would grip this jaw better.

 

[VicMallows]

On my Barlows (not sure without checking but I think they are 40s) there is a spacer which can be removed/repositioned to adjust for different sheet size.
FWIW I use 14mm braid-on-braid.

 

[geem]

On my Barlows (not sure without checking but I think they are 40s) there is a spacer which can be removed/repositioned to adjust for different sheet size.
FWIW I use 14mm braid-on-braid.

Thanks Vic. I tried 12mm, 16mm and 18mm. Didn't get much success. Will try 14mm and strip the top of winches to see if mine have a spacer