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Hey there. I'm looking for feedback, advice, knowledge, etc.

I recently purchased a used YCB-621. I love this horn. The problem is I've got sticky valves. It got the hydro bath and a valve realignment at a solid repair shop. I start playing it and everything is fine. After 10 - 15 minutes though the valves start getting sluggish/sticky. The shop used Al Cass. I have Ultrapure at home, so I disassembled the valves, thoroughly wiped them dry and then applied Ultrapure. Better for a while, then same thing.

What am I doing wrong? This is my first piston horn, so I'm kind of lost and could really use some help. Thanks!

Before reading this, check the next posting by Marty Nellan which is specific to Yamaha horns. Read on if still having troubles...

I had haunted-horn syndrome for quite a while in my Imperial.

It was caused by mis-alignment of the valve casings, created by torque in the valve tubing. In my case, the catch on my shoulder strap popped open and I didn't grab the tuba quick enough, so gravity took over ( ok, mea culpa, I dropped it on the way back across a field after a marching gig). I have heard you can get the same kind of problems if something heavy gets stacked on the case, or if someone sits/falls/leans/etc. on it (you may never hear about it, especially if it happens in the bandroom). Someone on here compared it to crush syndrome. The valves get pushed/deformed/bent a bit nearer to the bell (often not enough to be noticeable without careful measurement), creating a certain amount of torque in the valve and/or mouthpipe tubing. The valves may work just fine when cold, but after you have been playing a while the tubing warms up and expands a tad, so things twist far enough out of alignment to make the valves sticky, or even just a tad slow.

Having the valves aligned usually means having the valves adjusted vertically to align the valve ports with the tube-openings in the casings, and so would almost certainly miss this very subtle kind of problem.

I don't have strong enough nerves to do any of this stuff to a real instrument, but I've heard you can fix this by pulling the valves out away from the bell by a few thousandths of an inch, or by unsoldering some of the joints to let the torque relax, then re-soldering them. For my own goddess, I took her to a competent repair tech and he got the valves working very nearly perfectly - apart from the ghost. A couple of years later the mouthpipe stay popped off, which suggests that some of the torque wasn't fully released: I had the mouthpipe re-bent a bit, and soldered back on, and the tuba has been fine ever since.

Other causes I have heard about are residues of buffing-paste or tube-bending pitch left over in the tubing, which can be fixed by thorough cleaning, or flaws like badly cut valve guide slots, or faulty valve guides or springs. If all else fails, consider exorcism. Good luck.

johnfuente wrote:Hey there. I'm looking for feedback, advice, knowledge, etc.

I recently purchased a used YCB-621. I love this horn. The problem is I've got sticky valves. It got the hydro bath and a valve realignment at a solid repair shop. I start playing it and everything is fine. After 10 - 15 minutes though the valves start getting sluggish/sticky. The shop used Al Cass. I have Ultrapure at home, so I disassembled the valves, thoroughly wiped them dry and then applied Ultrapure. Better for a while, then same thing.

What am I doing wrong? This is my first piston horn, so I'm kind of lost and could really use some help. Thanks!

The Yamaha YxB621 valves have "too close" of a tolerance in them. I was fighting that for years on my YFB621 until I had a top tier repairman lap them. The slightest anything would otherwise cause them to hang up.

Marty,

Thanks for your reply. I’ve been cautious about lapping, it seems to be a polarizing topic. That said, I’m going to take your advice and bring my horn to my repair guy. I trust his opinion and he does great work. I’ll let you know what he thinks. Thanks again!

I just sent you a pm but it seems to be stuck in my outbox. I had exactly the same problem, happy to pass on what worked for me. Email or pm me.
Sasha Johnson