Godwin OHO pump help please

Can anyone help me please. I have a Godwin OHO pump with the piston seals in a rather sorry state. I have the pump out of the pump house and in a state of disassembly, but I am struggling to remove the pistons from the bores. I have got as far as removing the rod seals but cannot undo the brass "nut" that retains the rod seals and holds the pistons into the pump body. Should this be a brute foce job (brass permitting) , heat on the pump body to free the brass nut or is there a dark art to removal?
Any help most gratefully received.

Sam

I may be wrong but Godwin Pumps are still going goggle them there from Cirencester Gloucestershire
Jonesey

Thank you, I will try the phone number listed. I was a little sceptical as they seem to part of a massive multinational now, and I was a little unsure of whether they would have anyone who knows about proper pumps not these newfangled things they have on the web site

Have a look at the resource page in Stationary Engine magazine. A chap named Doug Newton from Fairford knows all about Godwin pumps.

Did not realize how close to home godwin was for me . Learn something every day

matt

Good news and bad news.
Good news first. After a touch of gas, I was able to disassemble the last part of the pump, and after a good clean up and a light hone of the bores four new seals were in place raring to go.

The bad news is that after putting the pump back in the pump house, I (with some excitement I may tell you) started the Lister up and turned the line drain tap off expecting water to start making its way up the hill to the tank. Unfortunately the massive pressure increase caused by having four seals all working instead of just one, hi lighted a point of weakness in the MDPE pipe that takes the water away from the pump. Luckily for me, my daughter without a thought for her own dryness shielded me from the huge shower of water that filled the inside of the pump house  

A new length of pipe and everything is working perfectly now but the Lister has not worked so hard for a living in a long time


Regards

Sam