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