Oil will leak out when the shaft is
bad. Under normal condition, there can be no pressure buildup in the pump,
because it is all open to the crank case via the oil inlet and relieve hole.
BTW, the shaft has a flat section on its running surface toward the pump for
oil feed.
----- Original Message -----
Sent: Monday, October
04, 2004 7:05 PM
Subject: [FlyRotary]
Re: OIL METERING PUMP
Subject:
[FlyRotary] OIL METERING PUMP
Richard;
Thanks
for input on this. That relieve hole looks very large and not likely to
blocked, especially on a newly rebuilt engine. Or am I looking at the wrong
thing; how does the oil get into the recess?
Oil
entering the pump can leak past the adjuster shaft if the seal was bad, right?
And what happens to the oil that enters the piston with the blocked exit
port as the piston moves to eject the oil? I was thinking it gets forced
back past the piston into the drive area where it can then leak past the
adjuster shaft, but I guess the feed oil is in that area anyway. Still;
it seems forcing the piston against the oil with no exit port would put high
stress on the drive plate, no?
Al
Al,
here is some more info on the OMP
oil feed.
Oil is coming into a recess in the pump
drive shaft. The thus formed cavity has a relieve hole as shown in the pic,
making the pressure in the cavity practically even with the crank case
pressure, depending someway on the flow rate. The roll pin in the relieve hole
is to make sure there is no air pocket in the cavity, which is connected to
the pump intake.
Each out put is driven by a
separate piston and two are together
per stroke. Each stroke is small enough not to create
a problem when you block a line off. It Would not hurt the pump if two
outputs are connected for double oil flow.
I hope it is clear, and not
confusing.