Unscrew the cap on the top of the valve and pull out the valve. Make sure it is clean and apply valve oil to the valve. Depending on how stuck it is and if the euphonium has not been played in a long time will determine how much valve oil you will have to use. After you have oiled the valve put the valve back in, making sure the guide is lined up, and then screw back on the top cap finger tight. If the valve is really stuck and you can not get it out you should take the euphonium to a Instrument Repair shop so you don't damage the instrument.
It depends on how stuck they are. If you can push them down easily, and they slowly come back up, or if they occasionally stay down then you just need to oil them.
However, if you have trouble moving them at all, or if they won't come back up after being pushed down, you have a bigger problem. You need to be careful not to further damage the instrument in these cases. Try unscrewing the bottom of the valve and give it a little push up from the bottom. You'll be tempted to wiggle the top of the valve back and forth, but doing so too strongly may just bend the metal.
In these severe cases, I would suggest taking it to a music shop to see if they can remove and repair the valve.
Valves for the trumpet were developed around the year 1800.
A standard trumpet(not a piccolo)usually has three valves. However, the higher-pitched piccolo trumpet has four.
The buttons on a trumpet are called valves.
They are called valves on a trumpet.
It's not recommended. Mineral oil is a bit too thick to be used on trumpet valves.
Valves for the trumpet were developed around the year 1800.
A standard trumpet(not a piccolo)usually has three valves. However, the higher-pitched piccolo trumpet has four.
Trumpet valves Motorized pumping valves are two sets of valves.
The buttons on a trumpet are called valves.
They are called valves on a trumpet.
It's not recommended. Mineral oil is a bit too thick to be used on trumpet valves.
A trumpet uses valves and is pitched higher than a trombone. The trombone uses a slide instead of valves, and is pitched between the trumpet and the tuba.
There are several types of trumpet; the most common is a transposing instrument pitched in B♭ with a tubing length of about 148 cm. Earlier trumpets did not have valves, but modern instruments generally have either three piston valves or, more rarely, three rotary valves. Each valve increases the length of tubing when engaged, thereby lowering the pitch. The trumpet is used in many forms of music, including classical music and jazz.
Valves
Trumpet.
The Trumpet is a brass instrument. Has three keys called VALVES.
mouthpiece, valves, spit valves, slides, tubes and bell