Probably the "Cumbria" model Smurf !!
My mates pump it was. The oil had gone milky coloured, and spouting a bit out. I told him it needed an overhaul and new seals. So he asked the local mobile pressure washer guy, fancy van like a franchise but thats all he does pressure washing equiptment, service , repairs. He looked at it and said.."its just a bit of oil in the water", i'll just change the engine oil for you. Can't remember what he charged. Couple months later on, its spewing foam out of the pump everywhere. Pressure washer guy again called, looks at it, pops side off and says i can get new seals in there without having to strip it all down on a bench. (no idea what seals he replaced).Changed oil etc. Then when my mates uses it foam is not popping out everywhere but there is no power, he tells the pressure washer fixer guy who then says..............well its an old pump, you don't know its history, its not worth fixing, the pistons are knackered i'll supply and fit a direct drive Hawk pump for you for £450 plus VAT. I advised him to forget it, then he dropped the VAT, i told him to forget that too. We just got a nice Interpump off Ben from Rutland pumps, or will have in the morning !!
I'll service the old interpump and gearbox myself. And thats what you get for listening to experts who put you off servicing a pump correctly. No idea why he wouldn't do it in the first place. Is it cost or something ? What does it cost for a proffesional overhaul of a pump ?