Sticking Rotary Valve

[Zaphod Beeblebrox]

I recently bought a new tuba. It's a Cerveny four four pitched in BBb. It has four rotary valves and has worked amazingly well up until about a week ago, when I started to have problems with the valves. Valve one sticks at one point in the rotation and clanks slightly when played at a fast tempo. Valve four works well, but I can hear a scraping noise when I press it down. I oiled both the valves and the linkages, but nothing has changed. I was wondering if anyone has any advice. Thanks.

[Dan Schultz]

You said the horn is fairly new. Unless there's been damage to the rotor... it's probably just buffing grit that's migrating through the horn and needs to be cleaned. It's not uncommon to have to do this with a new horn. Some Dawn, warm water, and a 'snake' should fix you up. If the problem persists... take it back to where you bought it or to a good repairman.

[Zaphod Beeblebrox]

Got it. Thanks a lot.

[iiipopes]

Last year my 186 developed a little bit of stickiness on the 1st valve. I cleaned the slides inside and out well, trying to keep any gunk from old slide grease from falling down onto the rotor. I unscrewed the bottom valve cap, filled the well with sewing machine oil (per Roger Lewis), soaked the top spindle bearing, and pulled the 1st valve slide without depressing the paddle to get some vacuum to draw up the oil onto the bearing. I took regular valve oil and dripped it directly onto the rotor to try to flush any gunk that may have been there between the rotor and casing, without popping the bottom plate to pull the rotor. I carefully (again, per Roger Lewis) checked all of my "S" arm linkage, applying 3-N-1 oil. It kind of got a little better, but not much.

After a few weeks of frustration, I had some summer informal concerts coming up. I played while drinking a significant amount of beer, and I think the tuba got bumped a time or two, but no noticable additions to the patina. I also had not noticed that the bottom acorn nut on the long, long threaded shaft that goes through the paddle mounts had vibrated off. THEN the rotor freed up! And it's done great since with minimal maintenance necessary to keep it that way, namely, more beer. Not bad for 40-year old rotors that have never been rebuilt!

[SousaSaver]

The clanking on a Cerveny could be the linkages. The arms that connect the levers to the stop arms on some Cerveny's are connected with threaded tensioning parts. If those parts have vibrated themselves loose even a little, that can cause noise while the valve is in use. These are somewhat pesky to adjust; too tight and your rotors will seize up, too loose and you have noisy action. There is a perfect "goldilocks" setting that will be fast, smooth and quiet.

The scraping sound is likely dirt somewhere in the horn that has found it's way to your rotor.

"Don't Panic." I know YOU get this joke.

[sousaphone68]

Mostly harmless

[Zaphod Beeblebrox]

Okay everyone thanks for the advice.I promise I won't panic.

[sloan]

Okay everyone thanks for the advice.I promise I won't panic.

You do have your towel, don't you?

[Zaphod Beeblebrox]

Of course I have my towel. It can, after all, be used as almost anything. I wouldn't go anywhere in the Galaxy without one.

[Mark]

A good, 3-pound sledgehammer will fix most problems.

[sousaphone68]

That's froody do you know where I can get a pan galactic gargle blaster or Babel Fish?

[Zaphod Beeblebrox]

Well as for the drink, it's served at most bars around the galaxy. As for the Babel Fish, a friend of mine, Arthur Dent, got his from Ford Prefect, who hitchhikes around the galaxy. If you can find Ford, he might have another extra.

[sousaphone68]

I will also need the number for the rehabilitation centre for the after drink care

[Tuba-G Bass]

Marvin the Paranoid Android knows how to fix this,
I think He's parking cars at the Restaurant at the End of the Universe.

[Zaphod Beeblebrox]

Hey everyone I fixed the valve. All I had to do was put a little oil on the valve cap; it was rubbing against the valve and causing it to stick. I feel a little bit stupid. I should have thought of that before. Oh well.