Spinnaker pole

[eddystone]

The piston at one end is seized though will release temporarily with lots of lubricant and application of mallet. How should I fix this?

 

[Poignard]

Remove the plunger, clean everything thoroughly, remove any corrosion, make sure the plunger is not bent and the spring is ok. Re-assemble.

 

[eddystone]

Presumably this involves drilling out the 4 rivets and removing end piece?

 

[Poignard]

As far as I can see, all you need to do is remove the "keyring" at the end of the piston and push the plunger out to the right.

 

[RJJ]

If possible I would seal one end of the tube then add acid of some kind. Start with vinegar, then if that doesn't work (add gloves and goggles) oxalic or hydrochloric.

Then lube.

 

[lw395]

As far as I can see, all you need to do is remove the "keyring" at the end of the piston and push the plunger out to the right.

I think you're right.
just scrape the crud off the parts (maybe gently clean the hole in the alloy with the right sized twist drill) and reassemble with lubricant of choice. Silicone spray is least messy, grease is most effective....

 

[Concerto]

It is worth trying boiling water before you start dismantling the plunger.

 

[eddystone]

If possible I would seal one end of the tube then add acid of some kind. Start with vinegar, then if that doesn't work (add gloves and goggles) oxalic or hydrochloric.

Then lube.

Seriously? Hydrochloric on aluminium?

 

[Spirit (of Glenans)]

Get it moving the give it a squirt of WD-40, then excercise it regularly as you would a seacock.

 

[awol]

While unlikely, it is possible the pin is bent. I would encourage dismantling by removing the split ring rather than adding acid or snake oil. If it jams it is for a reason and that needs fixed.

 

[johnalison]

I think you're right.
just scrape the crud off the parts (maybe gently clean the hole in the alloy with the right sized twist drill) and reassemble with lubricant of choice. Silicone spray is least messy, grease is most effective....

My Selden one is the same. Just remove the split ring and give it a clout. I use winch grease and it is an annual maintenance job.

 

[Stemar]

Seriously? Hydrochloric on aluminium?

A dilute acid eg brick cleaner for a short while won't do any serious harm, but I think the best way would be that offered by lw395

 

[eddystone]

The only split pin I can see is on the thin end of the piston for attaching the pull cord. Otherwise there is just a black collar round the piston where it enters the end casting - presumably some sort of retaining spring inside. Freeing it off is not difficult but it seizes up again after a while.

 

[awol]

That split pin is all that holds the piston in. Take it off and push the pin out complete with spring.

 

[Poignard]

See posts #2 and #4

 

[lw395]

The only split pin I can see is on the thin end of the piston for attaching the pull cord. Otherwise there is just a black collar round the piston where it enters the end casting - presumably some sort of retaining spring inside. Freeing it off is not difficult but it seizes up again after a while.

Yes, undo that ring and the piston should come out.
If you remove all the corrosion products and reassemble with some sort of lube, it should last longer between attention.
I have some clear ptfe-loaded grease I might use, or maybe just wax polish. I like wax polish for jobs like this because grease will find its way onto sails and lines, having acquired black staining properties from the ali compounds....
Short of re-anodising the end fitting or boring it out and bushing it to avoid stainless-ali contact, that's the way it is, I'm afraid!