Well, that's one way of putting it
The oil pump pumps the oil, and if there is no restriction then there is no pressure, just lots of flow. The main and rod bearings have fairly tight clearances and restrict the flow of oil, thus causing pressure to rise. IIRC, every line except the one feeding the mains (and thus the rods) has a restrictor in the line to limit the flow (which increases the pressure).
I'll have to check the manual later, but I think the rated pressure on the 650's is around 30 psi at 3k rpm, althiugh I'm not real sure at the moment, it could be higher. The 1000's run somewhere around 5 psi because of roller bearing cranks (very little restriction).
Quoted from my previous posts above:
As the oil warms up the thickness of the oil decreases, so pressure drops, although if pressure drops far enough to trigger a good sensor, then you do have a problem.
(4) Clearances exceed service limits (remember that 750 motor I mentioned?)
By clearances I mean any lubricated bearing surface, like the main, rod, and cam bearings.
But when you said the motor only had 13k miles on it, then that lowered the probability of bad bearings, it's still possible, but that made me want to check everything else first (expecially the easy stuff).
Post edited by: steell, at: 2006/04/15 03:03