Bad Valve Compression story

[TheConnsequence]

In short I bought a four valve horn, with great potential I might add, six months ago. Not nice looking by far, but it did have potential. After playing it for a few months, I realized that the sound was actually a bit stuffy and airy, so I asked a few people who knew how to test valve compression. To my fright, I had been told that my horn had horrible compression. When the first, second, and third valves were pulled out, there was no pop. The fourth was fine. So I went to a repair shop, asked the guy if he had any thick valve oil. He said he did and gave me some Hetman 3. It helped, the third valve. The first two were still horrific. So I went to the local Walmart, and bought some three in one oil. This definitely helped a lot, but left the second one very sluggish, and eventually seeped into the third and fourth valve, which was a problem. But sadly, the first valve was still holding the instrument back, because the 3-in-1 oil did not make the movement of the first valve any slower, which meant there was still a horrible leak. Mineral oil pretty much solved the first valve's leak, but seeped into the other valves, so I just went back to using 3-in-1. I did continue using the horn whenever a tuba was required of my own, but the horn still was at maybe 65% of its potential. Last week though, I had this insane idea that pretty much any tubist or repairman would probably slap me from having. Petroleum jelly. So I wondered for a few minutes if I should try this, since I just got through with bathing the horn and definitely did not want to go back and do it again because of the valves. I tried it anyway. IT WORKED! By some crazy odd, petroleum jelly solved 95% of the compression issue in the first valve, and some in the second and third. So for the last week, I've been lubing my valves with PJ (not PB and J, although that would be pretty appetizing come lunchtime) since then and I have not had many problems other than less-than-sluggish, but still not as fast as they could be valves. Any disagreements? Agreements? Slander?


--Justin H. Coker
Yulee, Fl

[Dan Schultz]

I am not a big fan of using petroleum jelly on slides, etc. I can spot a horn that has had PJ used on it in an instant. The slides are blackened and are usually stuck after being left in one position for a while.

[Donn]

I'm sure there are thick lubricants designed more strictly for mechanical applications. I'd start with ordinary motor oil, which some people do use regularly for piston valves, mixed with lamp oil. I wouldn't expect much from 3-in-1 oil.

[Dan Schultz]

I'm sure there are thick lubricants designed more strictly for mechanical applications. I'd start with ordinary motor oil, which some people do use regularly for piston valves, mixed with lamp oil. I wouldn't expect much from 3-in-1 oil.

+1

[Phil Dawson]

Try STP it should make everything go faster and maybe it wont burn as much oil, Phil

[Dan Schultz]

Try STP it should make everything go faster and maybe it wont burn as much oil, Phil

Jokes aside... a drop or two of STP to three or four ounces of lamp oil makes a 'killer' oil for worn pistons.

STP is also VERY good for slides.

[sousaphone68]

 by bloke » Fri Dec 06, 2013 10:29 pmWhat about raw honey mixed with extra-virgin olive oil ?Isn't a natural/organic approach best?

Just when I finally secured a supply of rancid bear grease

[ppalan]

Try STP it should make everything go faster and maybe it wont burn as much oil, Phil

Jokes aside... a drop or two of STP to three or four ounces of lamp oil makes a 'killer' oil for worn pistons.

STP is also VERY good for slides.

Dan, your comment sent me searching for "Lamp Oil". I have no experience with this stuff. In terms of use as valve oil, does it make a difference if it's paraffin-based or kerosene-based? Could the STP be mixed with either one?
Pete

[Dan Schultz]

.... In terms of use as valve oil, does it make a difference if it's paraffin-based or kerosene-based? Could the STP be mixed with either one?
Pete

The terms paraffin and kerosene are one in the same. Non-synthetic valve oils are just highly refined kerosene/paraffin.

You want to get what's billed as 'ultra-pure' lamp oil... one that does not contain citronella or fragrances.

Yes... STP will blend with ultra-pure lamp oil. It doesn't blend immediately but will go into solution with a bit of shaking.

A 'drop' of STP is difficult to describe. I usually just dip a screwdriver into the STP and 'skin it off' into the bottle containing the lamp oil.

If you have the patience... you can keep STP in a needle oiler and dispense a drop onto a piston and then apply the lamp oil. If the valve feels sluggish... just apply some more lamp oil.

[royjohn]

If the horn has great potential, perhaps it's time to bite the bullet and get the valves rebuilt. Your thick oil shenanigans may allow you time to save up to have the horn really put right.

[TheConnsequence]

Is motor oil and STP oils thicker or slightly thicker than Mineral oil? I know lamp oil couldn't be.

The horn means a lot to me, but then again it plays well as it is and I'm afraid a valve rebuild would make it too different to get used to.

[Dan Schultz]

A valve job certainly won't hurt your horn... only your wallet. I think you would be quite pleased with the results.

Go for it!

[k001k47]

are you sure it's not a crack or hole?

[iiipopes]

I used to use petroleum jelly on valve slides. But petroleum jelly is hydrophillic, and that is not good; it provides an environment for corrosion to occur.

For worn valves, I use pharmaceutical grade mineral oil added to conventional valve oil. I take an ounce bottle, and add a drop of mineral oil at a time, mix it up, and apply it to the valves and repeat until I get the correct viscosity that will seal the valves but not impede valve travel.

Please don't use petroleum jelly. In the long run it will make things worse, not better. Corrosion and having to clean thick crude out of the knuckles is not a pleasant chore.

[Lee Stofer]

I have this unusual idea about worn valves, where I remove the valveset, clean everything very thoroughly, send them to the best rebuilder in the business, and in 4-6 weeks, voila, the valveset returns, better-than-new. The valve casings are honed to perfectly-true, the valves have been prepped and plated, surfaced to perfectly true on a centerless grinder, and then replated if needed to build them up to the point that they can be hand-lapped to perfection. When reassembled into the instrument, and the instrument is thoroughly cleaned, suddenly the instrument with newly-rebuilt valves is exquisite. The result is an instrument that plays like new with generally less than 10% of the cost of a new instrument.

Finally, do not be afraid that the instrument will play too "differently" from how it does now. With the loose valves, the instrument is terribly inconsistent as the level of sealing in the instrument changes by the minute, or by the latest attempt to make it seal well-enough to play. Imagine that same instrument playing very consistently the same, day after day, even if you only oil the valves once a week.

[iiipopes]

+1 What Lee said! Yes, getting the valves rebuilt is the preferred solution. But time and money constraints must also be acknoledged. That means my method of adding mineral oil to conventional valve oil is, well, yes, I have to use the pun, and it's only intended as, wait for it....





















A stopgap.

[royjohn]

Hi Lee,

While I'm not a brass repair tech yet and don't even play one on TV or in my bathroom mirror , I thought I was familiar with all the steps in valve rebuilding. So when your dream valve rebuild included "surfaced to perfectly true on a centerless grinder" I did think it was a dream, as I don't know anybody who has the means to do this. Perhaps Anderson does and you can enlighten me as to what this means vs just using wood blocks as sold by Ferree's to round the valve cylinder. Does this actually work better than the old lapping method with pumice or a suitable diamond grit?

I'd also be interested, and I think others would be, too, in an approximate cost for valve rebuilding. I know there are variables such as how difficult it is to remove the valve casings from the horn, but perhaps you could give some guidance on what folks would spend should they want to ditch their vaseline, motor oil or what have you and get a proper valve job.

TIA for all you do to make this forum a great place to learn. . .

[opus37]

I agree with what Lee said. I had him do that to a 1912 Martin Eb that has historical significance to me. Yes, it is a bit pricy, but every major repair is a "is it worth it" question. With that said, Lee took on my horn and fit it in his schedule. He is very busy so it took about 6 months. I wasn't in a big hurry either. The result was amazing. The horn plays significantly better than before (when I was using thick oil). A lot of things cleared up, it became easier to play and thus more fun. If you like your horn and it makes financial sense to you, I would highly recommend the valve restoration that Lee detailed. Have someone like Lee do it. Taking a tuba apart and putting it back together right is an art. You get what you pay for when you do this type of work.