Quote:
Originally Posted by David Herbert
The 30psi at 800rpm is the oil pressure generated by the pump. There is almost no pressure resulting from the pump actually at the big end. The pump gets it to the main bearing, from there it makes its way by centrifugal force.
|
It strikes me that the oil passing from the main bearing into the hollow crankshaft is having to fight against centrifugal force, although after that centrifugal force is certainly helping it get to the master rod brg.
Quote:
Originally Posted by David Herbert
Even at 800rpm big end lubrication is marginal.
|
Certainly - with a hot oil idle pressure maybe around 10 psi and weak centrifugal force, I can see that.
Quote:
Originally Posted by David Herbert
There is no oil supply to either end of the slave con rods, they are lubricated only by splash.
|
The attached extract from the C1 manual below shows passages for force feeding oil from the master rod bearing to the slave rod big end bearings.
Quote:
Originally Posted by David Herbert
Incidentaly the low compression ratio is effectively doubled by the action of the supercharger above about 1500rpm which is how it manages to make nearly 400hp.
|
Do you know what the boost is above 1500 rpm? The doubling of the compression ratio infers it is 10-15 psi. It seems such a small impeller for such a large engine, even with the 10.15:1 gearing.
Quote:
Originally Posted by David Herbert
You will have to completely dismantle the engine to make sure there is no swarf anywhere and to check / replace bearings that have been damaged.
|
We will be. And that brings up another problem - finding space for and keeping track of the parts!
Quote:
Originally Posted by David Herbert
Have fun, David
|
We will.
