We didn’t disassemble
the oil pump while I was there just the rotor housings and E-Shaft. And, no,
the filter wasn’t clogged at all. The only thing I could find in the filter
was a little tiny brass colored flake about every other pleat (maybe 20-30
overall).
I just think Dave is
scratching his head wondering how the bearing could be worn like that. I’m not
sure it was worn enough to cause low oil pressure – but then again I don’t
know how worn it needs to be for the pressure to drop off. So, I wouldn’t even
characterize it as “theory” at this point. It was just something to checkout
in the process of trying to track down anything that could cause abrasion. But
I guess if the PSRU drains to the pan (which mine does) there is no chance for
any big pieces to get by the screen and the
filter.
Thanx,
Joe Hull (attempting not to step in
it!)
Cozy Mk-IV #991 (In Phase1 Flight Test
- 10.9 hrs flown)
Redmond (Seattle), Washington
From:
Rotary motors in aircraft
[mailto:flyrotary@lancaironline.net] On
Behalf Of Tracy
Crook
Sent:
Wednesday, May 03, 2006 12:23 PM
To: Rotary
motors in aircraft
Subject: [FlyRotary] Re: Was Oil Pressure
and Now...
With all due
respect to Dave, this sounds fishy. Assuming there was
"a problem with the PSRU", it would not show up in bearings unless the
oil filter was completely clogged with debris or the oil pump had been damaged
(was it?). From your description of the filter, it was far from
clogged.
Debris from the
drive can only go to the oil pan. Anything that made its way past the
oil pickup screen and through the oil pump would have to then go through the
filter before it got to the bearings. Is this the theory or
is there another explanation?
Tracy (tired
of hearing from Dave that my drives can't
work)
Subject: [FlyRotary] Re:
Was Oil Pressure and Now...
>We'll all be
interested to hear what they find.
Went to see David
Atkins yesterday. He continues to be a good person and business to deal
with. He took the time amidst the chaos to have the engine completely torn
down and inspected piece by piece as it was disassembled – while I was
there. It all looked pretty good until the front housing E-shaft bearing.
There was definitely some abnormal wear there and some scuff marks on the
E-shaft. There was also some wear on the center bearing but just on the
forward 1/10th of an inch. He’s going to replace the bearing and
rebuild the engine and then check the oil pressure.
He suggested I look
for any source of chips or anything coming from the PSRU. Something caused
that front bearing to get worn way too quickly and he suspects there may be
a problem with the PSRU since we didn’t find anything in the engine that
looked like it was shedding metal.
I’ll try to get up
to the hangar in the next couple of days to retrieve the RD-1B and bring it
home for disassembly and inspection.
ThanxAll,
Joe
Hull
Cozy Mk-IV #991 (In Phase1 Flight Test
- 10.9 hrs flown)
Redmond (Seattle), Washington