[C320-list] Maintenance Tip: Mast Step Blocks/Studs

[Jeff Hare]

Hi All,

With a number of new owners on the list this year, it's time to re-broadcast
the important annual Mast Step Block maintenance tip.  I can't remember if
the newer MKII mast steps are the same as the older ones, so someone else
can comment there.

Apologies for those who've heard this before, but it's important and not
always very obvious.

The turning blocks attached to the base of the mast have SS studs that screw
into a SS nut that slides into a slot under the mast step.  Since the nut
and the stud are Stainless, and the mast step is Aluminum, the studs will
corrode against the mast step plate and freeze up, faster in salt water.

They need to be able to turn freely to keep from being bent under load.  I
suggest you unscrew each block (counter clockwise of course),  and slide the
nut out of the slot with a screwdriver.  Coat the stud and threads and the
whole nut with "TefGel" anti-sieze/anti-corrosion grease and reinstall them.
Without doing this they will corrode and freeze up and may require removing
the mast and mast step to fix them!   After that, liberally spray the
bearings of each block with "Sail Kote" or your favorite dry lube.   

 

To do this simple maintenance job, you do not have to have to remove any of
the lines, just loosen the lines to provide some slack.   When you screw
them back in, screw them in all the way with your fingers until they stop
then UNSCREW them one full turn.  This allows the blocks to pivot easily and
stay fair to the pull of the line.

 

I didn't do this last year (maybe it's been 2 years?) and one of them was
right on the edge of being frozen up.  Took a bit of effort to get it freed
up.  I saw serious case on a C380 where the owner snugged up all the studs
so that they didn't pivot at all and under load, some of the Garhauer blocks
bent because they couldn't swivel to align with the rope under tension.  On
top of that, most of the studs had corroded solid to the mast step.  The
mast had to be pulled, the step removed and the studs had to be removed by a
machine shop.  This was on a boat only 4 years old.  Don't let this happen
to you! :)

-Jeff Hare

#809