K5 1 unloader valve

by Pete McAdam
(Northampton uk)

Very good flow sensitive unloader..

But only lasting 3 weeks at best.
My machine is running 8/10 hours per day.
Simple enough to change..
Simple enough to set up.
Once set.. 2200 psi 17 lpm with ease..
2 days later..
Power dropping..
Re adjust unloader by loosing lock washer. Turning bolt towards + test machine.. All good.
Now may last another 2 weeks. Then need again.
Then finally nothing left to adjust.
Power drop by maybe 60% but still bypassing back to tank. Still works..
But power right down.

I have loads of scrap ones.
Going to take one completely apart Saturday/ tomorrow.. See what is going on inside. Is it the spring.. what..

I've got filters on water going into my tank.. 12 inch filter going out.

I've tested see if pump.. nope still sucking.. no leaks.. valves in good condition. Crank case oil clean.. ceramic's not cracked.

Next option if cant find problem.. bite the bullet go stainless steel unloader..And assume these K5 are not heavy duty industry. Just expensive rubbish.

Comments for K5 1 unloader valve

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Apr 01, 2017
K5 1 unloader valve
by: Doug in s.d.ca.

This is new to me -

But I see there are a couple of youtubes on these.

At 17lpm, maybe you should be using K5.2?

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