I have had to replace a broken reefing line a few times now – twice on my 1260 and recently on our new 1370. The hard part is feeding the new reefing line through the boom – and particularly getting it through the correct channel at the mast end of the boom. It took me quite a while to figure out how to do this – but eventually came up with a technique that seems to work.
At the neck of the boom – there are 3 separate channels with dividers that run inside the boom for aprox 200-250mm. Each reefing line runs through one of these channels. This means that you cannot simply attach a mousing line to one of the other reefing lines as the mousing line will be pulled through the incorrect channel. What you need to do is somehow feed a mousing line inside the correct channel – then ‘hook’ it back out through one of the other reefing line channels – so it can then be tied off on that reefing line – then pulled through the boom.

First – I created something that I could insert down one of the channels with the mousing line attached – that I could hook and pull back out the next channel. I used to large 12″ cable ties – which are ideal of this purpose.



The rest is pretty straight forward – simply pull the reefing line through the boom with the mousing line attached – you need to remove the blocks at the stern end of the boom – and use your hook to fish out the mousing line.
Good luck – hopefully this helps.
I did have a very long electrical cable mousing device with me on the 1370 but we were not able to get that past several of the obstructions inside the boom – despite trying for several hours.