Cleaning Inside Axial Valve Casings

[OldNobody]

I just picked up my XO 1240RL-T again, for the first time in six, or so, years. I wasn't surprised to find the valves sticking.

I disassembled everything and found the valve cores to be clean, except where the insides of the valve casings had left some corroded brass on them in a couple of places. I cleaned them smooth with Dawn and my fingernail. They are not plated, but seem to be a cast aluminum (light metal) that was polished smooth.

The valve casings had a couple of areas where some green corrosion had built up a little, but were mostly darkly discolored in various areas.

I packed the valve casings and surrounding tubes with paper towels, carefully poured some white vinegar in to soak the paper towels and let the casings sit for an hour or so. When I pulled out the paper towels and washed the casings, most of the discoloration was gone, except there were a couple of areas where I could still feel the green corrosion.

I used some bronze wool and valve oil and got those areas smooth.

I cleaned the undersides of the valve caps with a wash cloth and vinegar, then used the bronze wool and oil. There is still a little dark (now lightened somewhat) discoloration here and there, but I can't feel it at all.

Do I need to be concerned with removing every bit of discoloration inside the valve casings and under the valve caps, even if they have been cleaned to where I can't detect any roughness or unevenness? (Is the only real answer to this question, "Put it back together and see"?) I've always cleaned and maintained my instruments, so I don't know what these things would look like after a professional cleaning.

I'm also thinking of using my Hetman's Light Linkage Oil on the valves, having read where some members have had success with thicker lubricants on axials. It's only slightly thicker than my Hetman's Light Rotor Oil.

Louis

[Bonearzt]

If they are working after your cleaning, you're done! I wouldn't try to get them sparkling shiny!!!

For my customers, I recommend a light piston oil for the insides of the valves, poured into the slide receiver. A couple of drops daily!!
And
A heavier viscosity oil on the spindles and a yet heavier oil on the lever linkages!

If your valves are still sluggish after your work, go see a tech!!

[OldNobody]

Thanks, Eric!

[Rrova]

I've used vinegar to clean the green stuff many times with great success. I always finish off by rinsing off the areas where I used vinegar with baking soda or some other fancier base to neutralize the acid. It may be possible that isn't necessary but it gives me piece of mind.

[brassmedic]

Just a warning to anyone who has an aluminum thayer valve core. Do not ever let acid touch aluminum.

[hornbuilder]

Thank you Brad!!
And to add further. The aluminum cores are the ones that are dark gray/black in colour.

Plated valves can be treated with the regular BIR cleaning chemicals (they are silver in colour