WTB: Speargun air pump.

[Popgun Pete]

Nemrod guns all use the same pump size, the decorative knurling on the tube changes on some models with the years, but it is still the same pump. The rubber seals on the pump rod piston age and crumble over time, so these need to be replaced with something else that can use an "O" ring as the original seals are no longer available. One thing that should be noted is a few hand pumps don't have breather holes as they rely on a piston seal lip reversing to draw air through the pump rod hole in the back of the pump, the Technisub pump is one of these. Nemrod hand pumps all have a breather hole on the rear of the pump tube body.

Some hand pumps such as the Nemrod seal the end of the pump tube against a washer in the back end of the gun by screwing down onto it. Others such as the Technisub seal the nose of the pump by pushing it through an "O" ring trapped in the gun's inlet valve body, while others such as Mares carry that seal on the nose end of the pump in a fitting that forms the front end of the pump. For some reason manufacturers decided to not use a universal hand pump fitting and few hand pumps fit anyone else's guns! This means that if you own a lot of guns of different brands then you will have a drawer full of hand pumps.

 

[Popgun Pete]

The Nemrod pump connection thread is M16X1 and the threaded length is slightly longer than one centimetre. The pump tube has an OD of 16 mm, the screw thread being directly machined into the pump body.

This photo shows the three main pump types; an open ended pump that seals onto a washer in the rear of the gun, a pump with a machined annular end that seals inside an "O" ring mounted in the rear of the gun and a pump (Mares) that carries an "O" ring that seals in a machined well in the inlet valve body of the gun. A gun which also uses the Mares pump in the LG Sub from Italy as they don't provide one of their own manufacture.

 

[cohenandy]

Great info, thanks, Pete!