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Hi Jim,

Do you have a photo? I have a 5-rotax 3050, with the 5th valve operated from the left. On this instrument, all five rotary valves are lined up in a row, with plenty of room to unscrew the top & bottom retaining covers (after removing the rotor arm).

If clearance is a problem, you should be able to tap the piston out through the top side.

Try using a 1/4 inch diameter oak dowel rod. Hold one end of the dowel against the piston's bottom bearing and lightly tap the other end of the dowel with a small hammer, which should move the piston toward the top. Almost immediately, the top retainer/bearing plate should come free of its light "press/tap fit" with the valve casing, allowing you to pull the rotor valve upward.

JCRaymo wrote:I don't have any photos but it is very clear that the valve will not come out through the bottom (cap side). I need to get it out and get it cleaned. I have not played since the holidays and my wife and I just had a baby girl so I have taken a leave from my band for now however I am subbing for them at an upcoming concert in a couple weeks.

The valve was getting sluggish at the last concert but it will work for this one. I will try to tackle it after the concert. The 5th v. on the Eb is no problem but the CC has very little clearance on either side.

Hi Jim,

By the "top," I mean the end of the valve that links to the rotor arm and linkage.

Obviously, you must first disconnect the linkage from the rotor arm. Then unscrew both the large retaining ring at the top and the bottom cap.

Next, by tapping on the valve's bearing shaft (with a 1/4 inch diameter oak dowel rod or similar non-marring tool), from the opposite "bottom" end, the top retainer/bearing plate should become free, permitting the valve to be removed.

On my big Kalison K2001, the 5th rotax rotor can only be pulled if the entire valve assembly is completely removed. Fortunately, on this horn, it is a relatively simple operation that consists of removing the leadpipe and unscrewing about a half dozen screws. Although I have been meticulous about rotor performance on past horns, I have usually only needed to actually extract the rotors about once every two years. Keeping everything clean and well lubricated, and not eating right before I play, (and if absolutely unavoidable, thoroughly rinsing out my mouth several times) seems to allow me to only worry about keeping the spindles (both top and bottom) lubed for regular maintenance.

Dean E wrote:Obviously, you must first disconnect the linkage from the rotor arm. Then unscrew both the large retaining ring at the top and the bottom cap.

Next, by tapping on the valve's bearing shaft (with a 1/4 inch diameter oak dowel rod or similar non-marring tool), from the opposite "bottom" end, the top retainer/bearing plate should become free, permitting the valve to be removed.

Dean, I think the issue is that there is no clearance behind the rotary valve for the rotor to come out even after you drive out the rear bearing plate. I've seen this on some tubas, particularly piston tubas with a fifth rotary valve, and wondered about the workaround, but can't suggest anything in this case since I don't have eyes on a 3050. Is it possible to create clearance by removing tuning slides?

It might even be an issue on my Yamaha 621 F tuba, but so far I've managed to keep it working fine for 17 years I've owned it without having to take it apart myself (I'm sure it's been apart when I've had it chem-cleaned). Next time I'm next to it, I'll look and see.

Rick "who can usually keep a rotor working fine without disassembling it" Denney

JCRaymo wrote:Yes I think Dean has it right. I just was not sure if the valve would come apart from either end. I just didn't know enough about rotax valves. I think it would be impossible without a torch to get it apart the traditional way out the bottom but there looks like there might be just enough room to get it out from the stem side. That is if I am very careful and don't slip up.

Okay, I'm confused. What you described and what Dean described don't seem to me the same thing. His words seemed like the normal way rotary valves are disassembled. The backside bearing plate under the screw-on cap is a press-fit, and is driven out by the rotor as a result of tapping on the protruding rotor stem, which is on the linkage side of the casing.

Your words suggest to me that the rotor will only come out on the linkage (stem) side of the casing. If that's the case, the it's the front bearing plate that must be removable, and hammering on the rotor stem pushes away from that plate and won't drive it out at all.

I'm for sure misunderstanding somebody.

Rick "(not) seeing ships passing in the night" Denney

JCRaymo wrote:

Rick Denney wrote:

Dean E wrote:Obviously, you must first disconnect the linkage from the rotor arm. Then unscrew both the large retaining ring at the top and the bottom cap.

Next, by tapping on the valve's bearing shaft (with a 1/4 inch diameter oak dowel rod or similar non-marring tool), from the opposite "bottom" end, the top retainer/bearing plate should become free, permitting the valve to be removed.

Dean, I think the issue is that there is no clearance behind the rotary valve for the rotor to come out even after you drive out the rear bearing plate. I've seen this on some tubas, particularly piston tubas with a fifth rotary valve, and wondered about the workaround, but can't suggest anything in this case since I don't have eyes on a 3050. Is it possible to create clearance by removing tuning slides?

It might even be an issue on my Yamaha 621 F tuba, but so far I've managed to keep it working fine for 17 years I've owned it without having to take it apart myself (I'm sure it's been apart when I've had it chem-cleaned). Next time I'm next to it, I'll look and see.

Rick "who can usually keep a rotor working fine without disassembling it" Denney

Hey Rick,

Yes I think Dean has it right. I just was not sure if the valve would come apart from either end. I just didn't know enough about rotax valves. I think it would be impossible without a torch to get it apart the traditional way out the bottom but there looks like there might be just enough room to get it out from the stem side. That is if I am very careful and don't slip up.

Thanks for all the help,

-Jim

I saw a picture on a couple of Willson sites, and could see the interference you're dealing with.

Two more things about the Rotax: Before disassembly, use a sharp scribe to put some match marks on the lower bearing plate and the end of the bearing shaft to avoid reinstalling the rotor in the wrong direction (180 degrees off).

As you reinstall the top bearing plate, observe the factory alignment marks. I use a very small crescent wrench to grasp the bumper stop and rotate the top bearing until the factory alignment marks are correct.

Play test before you run off to a rehearsal or performance. (Voice of experience-did I mention 180 degrees off?).