Changing the furling mainsail downhaul line

[Rortega46]

I am changing the furling mainsail downhaul line and having problems removing the old/existing line.  I assume to remove the line all that needs to be done is remove the mainsail, unscrew the line from the screw, remove the set/allen screw, and the line will come out.  Sounds simple, but...... the set screw is frozen in place and won't move. 

For those with experience changing the downhaul, what was your process? How to go about removing the set screw?  How to thread the new line through the furling screw? After threading the new line through the furling screw should there be a knot or something to stop it from being pulled out or does the set screw do this?

Thanks for your replies and suggestions.     

[Jim Hardesty]

I've had mine off.  No knot. You have the right idea.  Just try your favorite penetrating oil, mine is Kroil, just something much better than wd40.  You may have to try it a few times and let it penetrate, ie. over nights or days.  My only real suggestion is make sure to have 2-3 turns on the spool when the sail is fully out.

Jim

[Dave DeAre]

I changed mine several years ago. Used an impact driver. Worked for me.

[Rortega46]

Jim and Dave: 
I've been putting PB on the screw daily, tried whacking it with two different impact tools, then tried heating the screw and cooling it with water.  I've only succeeded in disfiguring the screw's head.  Kroil arrived by mail yesterday and I will continue daily treatments until I figure out the next step.  I'm afraid to disfigure the screw too much or drill it out for fear I could be forced to ultimately remove the furling screw which may involve taking the mast down.

Is it possible that the set screw is a reverse thread or there is some sort of backing nut (or something unseen) keeping the screw from breaking free?

If anyone has suggestions on where to go from here I'd love to hear them.   

[Jim Hardesty]

Randy, 
Keep trying the penetrating oil.  Another thing that comes to mind is a cracked allen screw.  They will sometimes crack at the recess for the allen wrench and when trying to turn the screw the crack opens up and locks up on the threads.  Happens when worn allen wrenches are used or wrong allen i.e. English tool in metric screw.  Sometimes it just happens.  Look at the screw with a magnifying glass and with a little pressure on the allen wrench and the glass usually at the corners.  If it's cracked it should show up.  If it is cracked I don't have an easy fix. Just need to work on it any way possible.  If enough is exposed vice-grips with one jaw on the crack.
Hope this isn't the problem and the penetrating oil works.
Jim

[Rortega46]

Jim

This set screw is more stubborn than a teenager.  I'll continue putting Kroil penetrating oil on the screw head daily and hopefully it will break loose before the head is ruined. FYI, I do not have an allen screw but a slotted head screw. Both screw types are listed on the parts list previously posted.  Since you did not comment, I assume there is not a reverse thread or some sort of backing nut (or something unseen) keeping the screw from breaking free.  If otherwise let me know. 

[Jim Hardesty]

Randy,
Shamrock had nothing fancy.  Just the end of the line crushed by the end of the screw.  As long as there is a couple of turns left on the furler when the sail was unfurled there is no need for the screw to be real tight.  One thought is to cut the line and pick out the line from the hole and get penetrating oil to both sides and maybe free up some of the pressure on the screw.  I wouldn't use much heat, not enough to melt the furling line and gum-up the threads, but maybe there is some locktite on the threads that need some heat to release.  Just throwing out some ideas.  It's realy a pain when a simple thing like removing a screw is an ongoing problem.  We've all been there.
Jim

[Mark Sutherland]

Rortega, my neighbor who owns a C350 just had this problem a few weeks ago, but I didn't ask him how he resolved it. If you post to the 350 site I'm sure he'll be happy to share his solution with you. Good luck.