Freeing pulley sheaves

[VallelyJ]

Hello--
The older aluminum and stainless fiddle blocks for my backstay tensioners are siezed--the plain nylon sheaves turn with difficulty if at all.
The rest of the blocks on the 30-year-old boat (recent purchase) are Shaeffers and seem in good shape. The ones in question are marked "Slater". (Never heard of them--have you?)
I've tried Kroil, PB Blaster, working them by hand and soaking in vinegar--no joy.
I am considering drilling out the rivets, cleaning up as necessary and replacing the rivets with stainless machine screws & red locktite. Any feedback on that idea?
Any other suggestions? They look good otherwise and would much rather spend my refitting money elsewhere if I could get them freed up again.
Thanks for any help.
John V.
Alajuela 33

[CS271409]

John,
Your idea sounds reasonable to me... after all what do you have to lose. Best case, your idea works and you sail happily for several more years with your old backstay tensioner. Worst case, you mess up the job or the sheaves still don't run free after the repair and you need to get a new one which is where you are now. I'd spend a couple of dollars and an hour or two to try out your plan. Get partially threaded machine screws if you can giving the sheaves a better surface to roll on. Inspect the screws and nuts regularly to ensure they don't back off. Loctite is pretty good.
Good luck... let us know how it turns out.