I'm not sure that would tell you very much, because it wouldn't be able to produce any back pressure. I would expect it to pee water out continuously even if (say) the by-pass valve were faulty.
It would confirm the supply is adequate.
But the OP has already said that he gets good flow (without a nozzle) when operating the trigger without switching the machine on - as one does to purge the pipework of air.
Just read through the thread, I still have a very old KEW Hobby, bought at the Ideal Homes Exhibition many many years ago. I also had this problem, and in the end it turned out to be using waterstop connectors on the inlet. Also had trouble with grit in the lance, had to buy a new lance, as the old one didn't lend itself to my style of DIY disassembly! :-)
Still in the garage unused now as it was bl**dy heavy to lug around, now replaced with a Nilfisk.
There is a big difference in flow with motor on and off though.
I can't work out why waterstop connectors are supposed to be a problem or if they are how. When connected the male spigot physicaly pushes the valve open, no way can it be sucked shut.
Maybe some people put waterstops at both ends of the hose and the one at the tap end is sucked too far open blocking the flow? Easy cure for that...
On the face of it, I've got to agree with you, there shouldn't be a problem. Except that from personal experience I can say there is! I can only think that the whole arrangement (the spigot, the rubber seal, the actual clearance when open) restricts the flow into the pump.
Have to agree on that they are not flow related when connected, as you say they are physically open when connected, irrespective of water.
Yep to be 100% sure ... connect up water hose, operate lance trigger but leave pump 'off' get continuous low of water, reaches about 30'
HomeOwnersHub website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.