02-01-2020, 01:58 AM (This post was last modified: 02-01-2020, 02:01 AM by Charles P.)
I have a recollection that someone clever (possibly Paul Bonewell) redesigned the "ball" part of the pressure relief valve to work better with a gear type pump/pressure fed crank. Memory tells me that it used a mushroom shaped replacement for the ball. I'm certain that I've got one somewhere but can I find it?
Does anyone have a photo or sketch of what the part looks like so that I can make a replacement?
Charles photos of pump assy including relief valve and spring, I usually make the valve adjustable by tapping the cap nut 5/16 bsf and turning down the head of a 5/16bsf bolt for the adjuster.
Terry.
About 10 years ago I made a remote PRV that mounts on the bulkhead. It uses A7 workings with a round ball in a simple aluminium block, with the bypass going straight back into an extended oil filler (mag engine). The original is blocked up solid so can't bypass.
It's worked perfectly for all these years but recently I've had odd fluctuations in pressure, suggesting something has worn or been damaged, hence the "back to basics" approach.
I'll investigate the problem and come up with a solution.
Chris pressure set at 65/70psi oil warm, adjustment range 40 to 100psi. Pressure 80 with cold oil always warm up engine before a run or keep revs down for first couple of laps as 100 not good for seals and filter. Terry.
