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Hi All,

I have the Yamaha 842 and I have a problem with valve 2/3 that is these valves seem to be sluggish the the 1st and 4th valve. One thing that I also noticed with these 2 valves is that when I loosen the button on top of the valve it spins the whole stem which then comes loose from the valve. Can anyone offer any suggestions for this or what the issue may be? Thanks!

It's a little difficult to interpret what you are trying to say. However... it sounds a bit like you have a valve guide problem. The valve guide should be located so the pin on the underside is in the SMALL hole in top of the piston. Then... tighten down the valve stem with the metal washer on top of the guide.

If there is not a small pin on the bottom of the valve guide... visit your local repair shop/music store for a replacement guide.

I guess to put it more simply, when I unscrew the valve button my whole stem comes loose with it as well too, not just the valve button.

Daniel8802 wrote:I guess to put it more simply, when I unscrew the valve button my whole stem comes loose with it as well too, not just the valve button.

That's really not that unusual. You need to use a plier to hold the stem and then take the finger button off. Then... properly locate the valve guide so the pin on the bottom of it is located in the SMALL hole in the top of the piston. Next... slip the washer over the male threads of the stem and screw it through the valve guide and into the top of the piston. Snug the stem down on top of the valve guide and washer. Put a little grease on the threads on the fingerbutton so it won't seize again. Put the piston felts over the stem followed by the cap. Then put the fingerbutton felts over the stem and screw the fingerbutton back on.

Now... you really have no need to take the fingerbutton off unless you are going to change the felts.

I emailed my local repair tech about this to see what he says. I've brought my horn in before and have had good service, so hopefully he can help out. My valves may also need to be lapsed since they all do not feel the same. The 2nd and 3rd valve feel stiff to use compared to 1 and 4.

Edit: they are also fairly noisy as well.