sluggish upright jack

[Eliot Lee]

Hello,

    I had an old upright piano (Ludwig) with very sluggish jacks affecting
repetition particularly in the high trebel.  Could this be from the coiled
jack spring?  I lowered the capstan and eased the keys still didn't help
much.  I noticed that there were no leads in the keys.

    Is this a sign that the wippen or the jack should be repinned?  What
about treating with protek?

Thanks for the help.

Eliot Lee