Hi Jarek, The vacuum from the engine holds the piston up when you apply power. If there is a hole, the piston will sit lower or if the hole is big enough won't lift at all! Either way you will get a restricted fuel/air flow to those two cylinders and they will be out of balance with the other side. A small hole = rough running. A big hole = very rough running.
regards Rob Rob Thompson 0429 493 828 On Sun, Nov 17, 2019 at 6:56 PM Jarek Steliga <[email protected]> wrote: > Greg, > > Thank you. This means that I was wrong in squarely blaming a tiny little > (barely visible) hole which I detected for the engine at times not being > able to rev up beyond 2000 RMP. I simply thought the diaphragm kept the > piston up for as long as the revs were higher and stayed there. My > detective work is back to square one. > > > Regards > Jarek > > > > On Sat, 16 Nov 2019 at 22:49, Greg Wilson <[email protected]> wrote: > >> The diaphragm helps lifts the needle when you accelerate. Failed or >> porous diaphragm will cause a lull in acceleration. I.e. If you slowly >> increase the throttle very slowly you should still get full revs. >> >> Ditto if you don’t lubricate the centre tube, which can cause the carby >> cylinder to bind when it’s lifting. >> >> My understanding anyway. >> >> >> >> >> Greg Wilson >> >> >> >> >> ---- On Sun, 17 Nov 2019 06:02:55 +1100 Jarek Steliga< >> [email protected]> wrote ---- >> >> >> >> Hello, >> >> In case some of you had this problem, what were the symptoms? >> >> Thank you in anticipation >> >> Regards >> Jarek >> >> >> >>
