Hills Mk 3 Hand Pump Issue

[oling]

I'm having a problem with a Hills Mk 3 hand pump which I'm using to pump up a HPA converted Ratty. For some reason when I've gone to refill the gun the upward stroke has become unbelievably stiff (to the point that it's impossible to pull it all the way to the top of the stroke) and then the downward stroke isn't 'biting' properly and it's not opening up the fill valve in the tank. Any idea what's going wrong here?

[12/200]

I know FA about them but sounds like a valve issue

[piggy589]

Residual pressure in the air reservoir exceeds that generated by the stirrup pump and human being operating it perhaps?.

[angrybear]

All you need do is think how it works,
The upward stroke sucks air in, the downward stroke compresses it, same happens at each stage.

If the upward stroke is difficult then one of the inlet valves is stuck, no air is getting in and it's trying to suck a vacuum in that stage.

Of course the tank valve is not opening because no air is being pumped to create the pressure to open it.

[Robet]

Sounds like it needs a service, probably a seal kit & lubrication.

Check out the web site http://www.airriflepump.com/

Rob

[robs5230]

Sounds like it needs a service, probably a seal kit & lubrication.

Check out the web site http://www.airriflepump.com/

Rob

Correct. Mine had the same issue. Hills sell the seal kits and its an easy job.

[Vermin Al]

Mine jammed. An indication of the problem was that the shaft was coated with rust, as was the outlet whip.

Got a replacement under warranty then got rid of and bought a 7l tank.