It’s time to change valve oils. This Ultra-Pure Valve Oil has been recommended to me. I just ordered a couple of bottles and also their Ultra-Pure Heavy Tuning Slide Lube.
I have been plagued with the main tuning slide on my pocket trumpet working it’s way out when I play high notes or fortissimo. I also have the main tuning slide on my Conn leaking some water along the slide (I had this since 9th grade). The Ultra Pure Oil’s heavy slide grease should remedy these problems.