So I just finished the JMT a couple days ago. The trip went extremely well and we had the times of our lives. The only problem was out of the three water pumps we had all of them experienced a problem. The MSR miniworks just sucks. I know there seems to be people that dont have a problem with this one, but I feel like it needs to be cleaned after a single nalgene is pumped and its always slow. We also had a msr microfilter hyperflow and it also wasn't working correctly the entire time. between the weird backflushing and valves, there were always parts that needed replacement.

As far as the MSR sweetwater, it worked the best of the three. It always pumped water smoothly and quickly. Its also easy to use and clean. All three of us ended up using it and had very little trouble. The only problem we had developed the last day on the trail. There was a leak that sprayed out of the top of the pump were the plunger enters the filter portion (not the relief valve thats designed to shoot water when its time for a clean). it started spraying a significant amount of water after a while. It looks like it could be a seal or something on the top of the filter. Does anyone know anything about this problem or how to fix it? I love the filter when its working correctly so id like to get it all fixed up for the next trip.

Thanks