Ian,

the OMP varies the amount of oil going into the valve.

 

I have determined that it just with RPM, and the throttle lever connection cuts the flow way back at idle,  but at not much above idle the flow valve is full open.

 

The valve is actually

a mini intake manifold in parallel to the main intake manifold. When the

rotor sucks the mixture in through the manifold, some of it is going through

the little vacuum hose and the little hole in the rotor housing picking up

what oil the OMP got into the valve. This oil is misted into the combustion

chamber.

If you have no valve, the droplets of oil will only produce an oil sweat at

the exit in the rotor housing and not doing anything. Sorry!

 

This is very interesting.  It is the first time I have seen an explanation of the valves, and it makes sense.  When I got my engine from Atkins, he said to simple cut off those valves at the injection ports, and block the holes.  

 

The oil still goes in and gets wiped away by the apex seals; which is primarily what it is supposed to lubricate.  Apparently Mazda had determined that having it “misted” in was a better idea.

 

Al