Below is my reply to a customer who has been sporadically working on his player piano for over five years.
One of the move difficult things for me to learn in my 40+ years as a service technician was figuring out what my customers wanted. Most often, they would say, "I just want it to play again." I would begin my reply by saying, "How well do you want it to play? Let me explain." Then I would demonstrate by pumping the pedals at different speeds, and as I did so, I would show them 'decent', 'good', 'better', and 'best'. Then I would explain the difference in costs between the four basic states of operation. Ultimately,they would make the decision as to how far to go with the repair or rebuilding.
I'm the same way with my own house. I know my heating bill would go down if I replaced all of my windows with the latest and greatest Anderson, Jeld-Wen, or Pella windows. But at what cost? If they cost $18,000 but would reduce my heating bill by only $180/yr, it would take 100 years to make it worthwhile.
With a player piano, it boils down to 'how hard do I have to work to play the music?' As I state somewhat at my site, pumping the pedals "should be" like taking a gentle walk on Sunday, not an aerobic workout. Your unit is very close to the 'workout' state. (Sorry, I have to be honest.) The only way I could determine how much more it would 'cost' (in terms of work that still needs to be done), would be to test each component and find out where it's leaking. Or, in some cases, determine where I can make improvements by doing maintenance work; such as regulating the piano and player actions.
Naturally, making these determinations requires a thorough understanding of how the entire system is suppose to work plus knowing how to effect the changes that will improve the performance of the machine. These skills are not easy to teach from afar. Most of them require 'hands-on' experience. That's why I worked as an apprentice in a piano store for three years before I started working for the public; and my mentor, who was 92, had worked on pianos his entire life.
In your case, if you were one of my service customers, I would probably suggest that the most cost-effective option would be to add an electric vacuum pump kit, and use it to compensate for the leakage in the system. Short of that, you are probably looking at rebuilding the valves.
For The Accuracy or Validity of the Statements and/or Opinions
Expressed within the Pages of the Player-Care Domain.
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