Assuming you have the shackle already spliced on the new halyard -- two basic options on how to proceed. If you are going to trash the old halyard, you can cut off the old shackle to save if you want, and use the old halyard as the messenger line to pull the new one through. I usually butt the two ends together and use duct tape to secure them together -- but tug on the joint really well before you pull it through. So butt the tail end of the new halyard to where you cut off the shackle on the old halyard, secure with a big piece of duct tape, and pull the old halyard up and through until the new one is in place. You can still use the old halyard line for something else in you want if it is in basically good shape.
If you want to keep the old halyard intact, you will need to pull the old halyard out first with a messenger line secured to the tailend of it. I use whatever small stuff I have for a messenger line, but make sure it is strong and flexible -- and long enough! Again, I attach the two together with duct tape, overlapping the small stuff on the old halyard if that thickness will go through the sheave. This time you will pull the old halyard out in the opposite direction from the first method. Once the messenger is in place (and I keep some tension on it to make sure it doesn't jump out of the sheave at the top of the mast) remove the duct tape and the old halyard, and attach the new halyard with duct tape. Pull the messenger line through until the new one is in place, and you're done.
Sounds more complicated than it is. Also, I use about a 6-9 inch long piece of duct tape to make sure it all stays together.
SailorMitchSailing winged keels since 1989.
1.20.09 Bush's last day the end of an error !! Hopefully we still have a constitution and economy left by then.
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