Sheave Replacement on ZSpar Mast Head

[cbsailor]

I need to replace both sheaves in my ZSpar masthead. Its a fractional rig on a Hunter 33.5 so I only have the main halyard and topping lift sheaves on the back of the mast head. The old sheaves are plastic and have started to disenergrate. The topping lift line is jammed on its broken sheave. The main halyard sheave is now starting to disentergrate. I purchased replacement aluminum sheaves from Rigrite and already have them. I would prefer to do the job without stepping the mast (I am currently on a mooring ball in Stuart FL). Has anyone accomplished this without stepping the mast and how did you do it? I have a Mastmate and have been to the top several times before. The problem is how to support myself (safely?) at the top while removing the load on the sheaves and its axle.

 

[Rich Stidger]

Oh boy, I wanna know this too!!!!

My sheaves are still original, but there will come a day......I can hardly wait to hear the solution.I just hope it doesn't involve a sky-hook..... They are terribly hard to come by.

 

[Paul Akers]

I Did Mine Last Summer!

The mast was unstepped, though, on my L37. I did the lower ones, but only 4 of them that are in the direct sun, all day long. If they are like the bottoms, there is a large clevis pin that acts as an axel to them. It "snaps" into place when placed all the way in. I removed the clevis remove the line by loosening it up and realligned the axel holes to re-insert it. That was all. The tools that I needed were a flathead screw driver to pry it out at the head, piers to pull the clevis out by the head and a can of spray lithium grease to lube it. You'll have to look at it, again, to re-asses the job without pulling the mast. Good Luck! Let us know how you make out!

 

[Don12364]

My Z Spar

In the summer I had similar trouble with the topping lift sheave on my Z Spar mast on my 376.I went to the masthead in a bosun's chair and had a length of line with me. There is a small hole on the crane extending aft from the masthead fitting so I put a 3/8"shackle through this and laced the chair to it as high as I could get it.The main halyard sheave and the topping lift sheave are on the same long 1/4" diameter (from memory) spindle but are separated by an aluminium plate.Once secure I had the halyard I was on released a foot or so and made fast again.Then took the halyard and topping lift off the sheaves and put them over the masthead fitting so that, if my light line failed I could only fall about a foot.Then I did the job.All quite easy and actually fairly safe - but it did give cause for anxiety as I am now fat and 72.Just do it.