Mast Sheaves

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Craig Illman

I've only had my boat about four months. Last Friday we ran a new jib up the track (Hood furler) and it was more difficult than I expected. It dropped rather easily, so I expect it wasn't the friction of the new bolt rope. I forgot to check the deck organizer and block at the bottom of the mast while they were unloaded to see if they were turning easily. If they turn out to be acceptable, I suspect the masthead sheave needs attention. My boat (#1150 1991) is fifteen years old, I have no idea what the POs might have upgraded or replaced.

Questions: What sort of life-cycle could I expect at the masthead? Is replacement going to be a "pull-the-stick" project?

SteveLyle

Yes, it's a 'pull the stick'.  The sheaves are in the mast head fitting, and you can't get them out without removing it, and you can't remove it without removing both stays and the upper shrouds, which I guess you could do, but you'd need a halyard to get you to the top, so while you're up there the top fitting is not coming off.  

Garhauer will sell you new ball-bearing sleaves, if you don't already have them.  '86 didn't, not sure about '91.

I pulled my stick and PM'd it 4 years ago.  My sheaves were simple bushes, still in great shape just more friction than the ball bearing ones.  The top of the mast is built like the rest of the mast - like a tank.  

Steve

Jim Brener

I have had the same problem for the last several times I installed the jib.  It was very hard to raise the sail.  With a friend on the halyard winch and lots of silicone spray, I got it up this year.  It could be the sheaves, something in the connections of furling sections or something else.  We are in our 4th season with this jib and it  was easy to raise for the first 2 times. , don't know what changed.  It comes down easy.  Will think twice if there is a major hurricane coming as I don't want to take it off and then have a hard time raising it, also don't want to leave it on in a big blow.
Jim Brener
Wind Spirit  1987  #504

Stu Jackson

One thing to consider if it comes DOWN easily are the extra blocks and friction used to get it up, like the aforementioned turning blocks and deck organizers.

I noted the used of the halyard winch to get the jib up.  In lieu of using a winch, why not just raise it from the port side of the mast?  With our double line mainsail reefing lines and a cunningham, the port side stoppers, deck organizers and fairleads are all used up anyway.  Also, since we don't drop our jib often, it appears that there may be no need to use the port side to bring the jib halyard aft.  After all, even if it's run aft, what's it doing all year?

We just cleat off the jib halyard at the base of the mast on a cleat.

Try raising the jib from the mast and see if that helps, then you may reduce your concerns about the masthead sheave.  If the friction disappears significantly, at least what blocks that are left you'll be able to get to.
Stu Jackson, C34 IA Secretary, #224 1986, "Aquavite"  Cowichan Bay, BC  Maple Bay Marina  SR/FK, M25, Rocna 10 (22#) (NZ model)

"There is no problem so great that it can't be solved."

Ron Hill

Cill : You are experiencing what most all of us have.  
You have a 3 nonball bearing sheaves to increase the friction - one at the top of the mast, one at the base of the mast and one in the deck organizer(turning block).

You can get bb sheave block replacements from Garhauer for all 3 and immediately replace the ones at the base of the mast and  the deck organizer.  Then when you pull the mast sometime you'll have the mast head halyard bb sheave ready to go.

If you spray some of the alcohol based teflon (West Marine) in the head stay track guide for the head sail - it will help the sail go up a little easier.  The alcohol base won't leave a stain on the sail.
Ron, Apache #788

Craig Illman

I expect now that it's just the cumulative friction of the three sheaves and the bolt rope. It doesn't "jump" too bad at the mast.  I guess replacement of the deck organizers and mast base blocks goes on the list of things to replace/upgrade. I guess when it has to be hauled out the next time to do the bottom, we'll pull the mast and deal with the top.

While I don't have anything yet to contribute to the forum, I've sure learned a lot from going through all the postings. It certainly adds a lot of value to the class. I really appreciate all the contributions from the "regulars" here.

Craig Illman

tstrand

I replaced my masthead sheaves by tilting the mast down onto a stand I built. What? You don't have a tabernacling mast?

Gloating aside, this change made a huge difference in halyard friction. All of the original, non-ball bearing sheaves were very sticky. But more significantly we discovered that, when the PO installed the masthead wind sensor, he drove one of the mounting screws into the plate that separates the two genoa halyard sheaves. This cocked the plate to one side, which essentially made it a brake for the genoa halyards. Amazing they worked at all.

With the new ball bearing sheaves (plus new ball bearing turning blocks and deck organizers, all from Garhauer), the sails go up easily and almost drop TOO fast.
Tim Strand
Calico #572
Santa Barbara, CA

Ted Pounds

I had the exact same problem as Tim with the screw cocking the sheave separation plate (or whatever it's called).  I suppose it might be an issue on  (lots of?) other boats too.  You folks with problems might want to try a trip up in the bos'n chair.  If the separation plate is the problem you can fix it with the stick up.  Just a thought...
Ted Pounds
"Molly Rose"
1987 #447