ZK1 Lifespan

[cjs966]

I use a ZK1 unloader on my system but only get a maximum of 500 hrs on it before I notice a drop in head pressure and cycling into by-pass mode while under pressure, resulting in replacement of the K1. I have disassembled all of my used unloaders and have noticed wear on the side and end of the discharge valve. Any ideas of a possible cause or is that the normal lifespan of this unloader??

 

[tomtucson]

I couldn't get the Z1 to work for me at all. I got it because it is supposed to run any gpm up to 10. I've had thousands of hours on all the regular Z7's i've used over the years thats what I would recommend.