How To Align Rotary Valves 

Thank you for the tip. I hope to do a series on a sousaphone on Fridays as soon as I am done with a saxophone repad. I will try to do other tuba videos as the opportunity arises.

Check again for the marks on the casings. They may just be very faint. If there is no mark, line up the rotor bearing so that the mark is pointing to the levers and align the valves that way. If that does not work, you can pull out the valve slides and look down them. This is a little difficult to do on 1, 3, and 4. You can also use a small dowel or something to feel through the slide tubes to see when the rotor is aligned. I hope this helps, Art

@@TheBrassandWoodwindShop Thank you for the reply. Looking down the slides was tough simply because it was hard to see. The dowel worked pretty well though. Since I've gotten everything reassembled, I used the camera on my phone to see down the tubes. It's very close but still not perfect, and I'm still not sure the bearing plate on the trigger is clocked correctly. Sounds so much better though. I wonder why no manufacturers make a keyed bearing plate that can fit only one direction. I almost think my old horn from high school did. It was a rebuilt Holton H-179, but it had some custom Lawson components, including the lead pipe and valves. Loved that horn. Thanks again for your help.