Tracy Crook wrote:

David Carter wrote:

I, too, want an external tank of apex seal oil.

I've looked at the Haynes manual photos of the oil injection "pump" and
drawings of oil passages in "block".  Looks to me like the engine oil
pump pressurizes all the oil passages, one of which goes to the "oil
injection pump".  I infer that the "oil injection pump" is not a pump -
rather it is a "metering device" that meters engine oil at current
engine oil pressure.  Thus, to run an external tank, one would need to
separate the "oil metering device/injection pump", install brass plug in
engine caseand in corresponding hole in injection pump; then, drill a
new oil passage from the top of the injection pump body into the
existing oil passage, tap it, and install the line from an external tank
at that new hole.

Then we are faced with getting 75psi oil from the external tank to the
new hole in the injector pump.  The first solution that comes to mind is
an external tank like a jet aircraft hydraulic accumulator - i.e., with
a rubber diaphragm separating the inner chamber in half - with oil
reservoir on one side, with outlet to injection pump/metering device;
and other side being plumbed to a source of engine oil at its 75psi
pressure, say from a T fitting at the oil cooler or oil filter body.
The diaphragm prevents mixing of the two type of oil and transmits
engine oil pressure to the two stroke oil (Marvel Mystery oil, per Tracy
Crook) and the system should work just like a stock system.

David Carter

Good job of analyzing the situation David.  There may be even more to the
picture than this.  It is true that high pressure oil goes to the metering
pump but this might be just to lubricate the pump drive shaft & gear.  I
haven't had the time to study it close enough to see if the actual input to
the pump is at high pressure or not.  The "pump" looks identical to the
Mikuni metering pumps used on Rotax 582s which use gravity feed from the oil
tank.  Mikuni makes the Mazda part  too.

Tracy Crook   rws@altavista.net

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