Hi David,
Took a couple of pictures of the one I got at the auction. Also my old original Villiers pump to add context. The JAP pump has a nameplate on the cowling with the first number being 1943. Do not know if that is the date it was put together, or if it is a coincidence. Also do not know if Alcon purchased the engines unpainted, then painted them all over in one colour. Or if it was reconditioned at some point and it was then it received the lime green finish. Be good it anyone could shed more light on this. The most important thing though is to get it working again and from the time it was painted, do not think it’s done much work. The oil is clean and the lot number shown is from a different auction. So it was likely purchased then, either the just stored, or the new owner could not get it to go until the farm clearance sale when I got it.
Had to do a bit of research about pumps when the Villiers engined Alcon pump would not provide enough pressure after I purchased 7off Hunter MP2000 Rotators to replace rotaframes. It would not both atomize the water sufficiently and throw it to the radius specified. I needed 25psi minimum, ideally 40psi, but 30psi would be OK at flow rates of 6.1, 7.7 or 6.7 gallons per minute respectively. Not many small petrol pumps could do that. But then got a Honda pump that just about did the job. During this research I discovered that you need a minimum negative pressure of 20 ins Hg (25” is optimal) on the suction side. Got a negative pressure gauge and did some testing and it was then I could determine if a seal needed replacing. Am afraid the Alcon pump never achieved the minimum negative suction pressure, even with a new seal. I also found that a new Clark 2” pump that had been run without water in it many times had ruined it’s seal too. A quick test is to put the palm of your hand over the suction end and it should have sufficient pull to feel quite painful. Or the time it takes to start pumping and if yours does this so quick, the seals are good. The Villiers pump used to take 3+ minutes.
If my Alcon pump was in good condition and could produce 66ft head, this would equate to 28psi with very little flow. Obviously pressure reduces as the flow rate increases. Another problem I had with the Rotators was blockages to the nozzles, so had to get a filter. Am pumping from a well into 80m of layflat tubing and found even tiny bits of debris (mainly little seeds and slime) caused troubles. Such a system really needs a permanently fixed suction pipe and underground delivery pipes. I then acquired an Evenshower Oscillating Sprayline system and upgraded it by doubling the nozzles to 10off on 6 sections and replacing the original worn out cone type 3 port valve to a ¼” BSP ball 3 port L valve. It works really well. It only needs 12 – 15psi at 7GPM. Believe it will run on a recently acquired 1” Locin pump, or a 1½” Alcon pump. But I now run it with the Clark 2” pump hooked up to a Robin EY15 engine and after it has started to delivery water from the well. Reduce the revs to about a third. It then purrs along under little stress. It’s a stress reliever for me too, I find watching, smelling and listening to an irrigation system operating therapeutic.
Best wishes,
Grahame
