Yamaha GH actions require the insertion of a “rod” (as it’s referred to in the service manuals). Yamaha sells a specific tools—specifically part TX000671 (VCN03010) during disassembly. The rod blocks the hammers, relieving the pressure on the contacts and contact circuit boards, allowing you to easily remove and reinstall them.
The tool Yamaha sells (TX000671 / VCN03010) is a steel dowel, of a suitable length and diameter to conveniently fit between the hammers and the frame.
One day, when working on a CLP-645, I found myself in a pinch, and used an improbable substitute: The 48-inch Orange Ground Mount Reflective Rod (or common driveway marker)!
Not only is this the correct size to fit nicely in both the Yamaha GH actions, but I actually find it easier to use. The tapered, pointed end means it slips more easily between the hammers and the frame. It’s made of fiberglass, so it’s less likely to cause unintentionally scratches. And in fact, the far end even comes with a ready rubber bumper, just in case you lose track of it and whack a wall with it!
The TX000671 (VCN03010) currently costs $187.0 to the public on Yamaha 24×7, whereas the trusty 48-inch driveway marker costs $3.27 at Home Depot (prices as of 9/9/24). It’s an option worth considering!
