Freeing a seized block

Blue Drifter

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The block below (used on kicking strap) has seized, is there a recommended process to try and free?

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lw395

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Looks like a plain bearing block.
Alloy sheave?
I would soak it in hot water, then try to work the sheave.
Maybe take it around to Tom's and bung it in his ultrasonic cleaner while we go out for a pint.
You could try a plastics-friendly penetrating oil like GT85 but TBH, it's probably grown some serious corrosion...
If that doesn't work, I'd probably drill out the riveted over bit of the sheave axle and pull it apart.
Drill and tap the axle and re-assemble with a button head screw. It may not have quite the same SWL, but most blocks are over-specced on many boats.
 

William_H

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It looks a bit like it might have roller bearing to me. However might be just plain sleeve. As said to get force onto the sheave wrap a suitable sized peice of rope around the sheeve then jam the ends of the rope into a vice such that the ends are pulled together tightening the rope. You can then work the sheave to make it move. If all else fails grind off the head of the axle rivet and punch it out. The replace the sheave if necessary and clean up corrosion or whatever is jamming i tup. good luck olewill
 

reeac

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Wurth, sorry, worth trying my favourite deseizing spray - Wurth Ultra 2040 - which leaves a deposit of ptfe. My latest success is with the plunger valve which switches between bath and shower in our main bathroom. This is seldom used as we have an ensuite bathroom and it used always to seize , entailing dismantling to free it up. AOK since I gave it a squirt of Wurth.
 

sailorman

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It looks a bit like it might have roller bearing to me. However might be just plain sleeve. As said to get force onto the sheave wrap a suitable sized peice of rope around the sheeve then jam the ends of the rope into a vice such that the ends are pulled together tightening the rope. You can then work the sheave to make it move. If all else fails grind off the head of the axle rivet and punch it out. The replace the sheave if necessary and clean up corrosion or whatever is jamming i tup. good luck olewill
It will have a SS bush in the acetate sheave, a stitch in time n all that
 

Thistle

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How much is your time worth? And how much risk are you prepared to take with new rivets / screws / pits where corrosion has been removed etc?

Perhaps the best answer it to consign it to the spares box and replace it with a shiny new one.
 

William_H

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How much is your time worth? And how much risk are you prepared to take with new rivets / screws / pits where corrosion has been removed etc?

Perhaps the best answer it to consign it to the spares box and replace it with a shiny new one.

Ah the disposable society. Throw it my way if you do throw it. Call me old fashioned or scrooge but most blocks on my little boat have have sheave replacements. olewill
 

Aeolus

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Always amazed that the risk-averse people on this forum ever get into a boat- do they not realise that they could drown, be captured by pirates, be stranded on a sandbank, be hit on the head by a mussel dropped by a seagull….? And that they cannot eliminate all of these risks by buying new blocks?

Ideas on how to repair/refurbish equipment is just what this forum is all about.;
 

Blue Drifter

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Many thanks for all the suggestions - block is now free, turning easily, and will be put back into use. For the record it was a combination of boiling water followed by WD40 and working with rope that did the trick. So fortunately no need to resort to boiling in vinegar although this would have been next. Will add flushing and lubricating sheaves to routine maintenance for the future.

The forum never fails to come up with solutions and helps identify best practice, long may it continue.
 
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