Hi all, I have put this one on my build thread, but I am after a definitive answer before I go any further. In trying to bleed the oil pump on my nsr250, I cant seem to get rid of these tiny air bubbles. I am running the bike on premix, and I have taken the bleed screw on the top of the pump out, and I holding the oil pump pulley fully open. This amount of air wouldn't be acceptable in a brake system, but is this normal for the oil pump? Thanks,
Thought we already covered this? If the tiny bubbles being shown in the bottom picture are what you are worried about, remember there is more oil than air there. What about some clamps (or even wire) on the hoses, could be getting some air in there.
It is the tiny air bubbles im worried a out. The oil system isn't really something I want to gamble with, especially on a 2-stroke. I don't believe the air is being pulled in from the hose on the oil pump because its a very tight fit. I really want this motor to last because mc18 bits are getting quite hard to find these days
i think those bubbles should be fine the pump is positive displacement which mean oil will leak out of those pipes no suck air air has to be coming from the inlet side or the pump is on its way out and is internal cavitation is causing the bubbles to appear you could try another pump to see if it clears it or run some pre mix again
