Bill -here is one way you can start out with good pressure
and have it drop off - I reported this back a few years ago, but might be worth
repeating as its related to the oil pump shaft Key. Check this
link
Ed
Sent: Wednesday, September 29, 2010 2:18 PM
Subject: [FlyRotary] Re: Oil Pressure Loss
Chris,
I don’t know how much
oil should come out on cranking, but Lynn would probably know. Seems like it
should be gushing though, if under no pressure.
I am not certain what
could have happened to cause the oil to pump freely, then drop off. Could
pressure have been a problem, but was just noticed?? Maybe the keyway or
the suction pipe. I think it should turn out to be related to your rebuild
45 hours ago.
Bill
B
From:
Rotary motors in aircraft
[mailto:flyrotary@lancaironline.net] On
Behalf Of Chris
Barber Sent:
Wednesday, September 29, 2010 1:43 PM To: Rotary motors
in aircraft Subject: [FlyRotary] Re: Oil Pressure
Loss
Sorry, I have had
some major issues with notebook computer I usually use at home. Most
recently with the mouse freezing, so, I had to use three post that should have
been one.
I have NOT had the
engine apart. It has about 45 hours on it since I performed the latest
rebuild using mostly new parts (rotor & end housings, rebuild kit...old
rotors and e-shaft). It had been running damn good, good enough that I
thought I was really close to the DAR sign off and first flight attempt.
The RPM indicator drop was a residual issue with the EM2 I was working
on trying to tie up loose ends.
As I mentioned, I
would have not had noticed an issue just listening and watching the engine, but
while I was trying (unsuccessfully) to solve my RPM drop reading problem I
noted the OP flashing and the low pressure
reading.
I am getting some oil
coming out of the front of the engine and into the remote oil filter which is
located between the engine outlet and the coolers, however, I
have apparently not had enough pressure to move oil out of the
filter. I replaced the filter and the same thing occurred. Perhaps I
have not cranked the engine long enough to move it through the filter as it was
getting dark and I had not yet moved the spark plugs and was concerned about
damaging the internals and PSRU.
Even though I am
getting flow out of the engine when cranking with the plugs installed, I do not
know how much flow it is....it is steady, but does not seem all that strong, but
of course, the engine is only cranking and not running. Also, since I had
no oil flow, I was concerned about cranking it without oil getting to the engine
and PSRU. I hope to get out to the hangar later today and continue my
checks with the plugs removed. I am not too hopeful though, it seems
as if it must be an internal issue, especially since the mechanical gauges
I hooked up also showed low/no pressure.
I agree, I do not
wish to tear down the engine, as I have a lot installed on top of it, plus the
PITA of opening the dang thing up. However, I have gotten pretty good and
uninstalling and reinstalling...(of course, apparently not good enough to
not have a problem). The process has gotten much faster as I have become
more methodical.
Dave mentioned some
of the issues we know about with keys and retaining clips. While something
like that could certainly be the problem, I am certain I addressed these very
items, even though possibly not well enough. If you would have asked,
I would have thought it was good, but now the evidence will
tell.
I have removed most
the hoses to check for obstructions and have yet to find any. Again, the
oil is coming out of the front of the engine in a stream but low pressure with
simple starter cranking, but as of yet has not made it past the filter, which is
the first "event" in the chain.
Do we know of a way
to determine how much oil should be flowing with simple cranking...such as "x"
amount into a jar in "y" time cranking? Yeah, grasping at straws...but I
am trying to get use to the idea of pulling the
engine.
From: Rotary motors in aircraft
[flyrotary@lancaironline.net] on behalf of Bill Brwhadburry [bbradburry@bellsouth.net] Sent: Wednesday, September 29, 2010 12:00
PM To: Rotary motors in aircraft Subject: [FlyRotary] Re: Oil Pressure
Loss
Chris,
Did you just have your
engine apart? If so, did you have oil pressure after that? Oil
from the pump comes out of the lower front housing and goes to the cooler.
Did you check to see if oil is coming from the first opening after the
pump? If it is not, the problem is inside the engine, if oil is coming
from the pump, the problem is outside the engine. Cooler, filter, hose,
etc, don’t tear it down unless you have to. If you didn’t use a
mandrel when you made up your hoses, you could have a sliver of the inside of
the hose blocking the oil flow.
Bill B
From: Rotary motors in aircraft
[mailto:flyrotary@lancaironline.net] On
Behalf Of Chris
Barber Sent:
Tuesday, September 28, 2010 11:26 PM To: Rotary motors
in aircraft Subject: [FlyRotary] Re: Oil Pressure
Loss
Oh, and maybe this is
too obvious, but when I drop the pan, what should I be looking for. Yeah,
large metal shards I would figure out, but if it is not that obvious, where do I
need to focus. The pressure gage?? The pump?? Something
else??
From: Rotary motors in aircraft
[flyrotary@lancaironline.net] on behalf of Chris
Barber [cbarber@texasattorney.net] Sent: Tuesday, September 28, 2010 10:11
PM To: Rotary motors in aircraft Subject: [FlyRotary] Re: Oil Pressure
Loss
Geeesh...the mouse
froze again.
To continue, I got a
moderate, steady stream of oil coming from the remote filter mount. So, I
had some flow. I then went to the end of the hoses where it re-enters the
engine after flowing through the two oil coolers. Well, here there was no
joy. No oil coming out. I did refill the filter before I reinstalled
it and cranked the engine for quite a while to no avail. Next, I unhooked
a few of the other hose connections past the filter and still no flow when
cranking. Finally, I checked all the way back to the filter outlet and no
oil would come out. I changed to a different filter and still no flow from
out of the filter. So, I have some flow....not a lot into the filter buy
none out.
I HATE the idea of
dropping the pan (will be a real pain) to check the oil pump and pressure gage,
but I am not quite sure as what else to check at this point. When I return
tomorrow, I will remove the plugs to take some of the stress off the starter and
see if I get flow out of the filter. I am also concerned now that I
have been cranking the system long enough that some important parts are
not running with a lot of needed oil, such as the PSRU
etc.
If I would have just
happened to look at the OP gauge, I would have never known there was a problem
as the engine "sounded" strong and smooth and continued to do so when I started
it to test my pressure after discovering the problems.
Hopefully this will
be a bit more directly answered by the engine guru types on the list since
it is not specific to Tracy's electronics.
Please, what else
should I check, I am about at the end of my testing skill set. Also, what
say ye as to what the problem "sounds" like????
From: Rotary motors in aircraft
[flyrotary@lancaironline.net] on behalf of Chris
Barber [cbarber@texasattorney.net] Sent: Tuesday, September 28, 2010 9:59
PM To: Rotary motors in aircraft Subject: [FlyRotary] Re: Oil Pressure
Loss
Aggg. I need a new
computer. The mouse froze and the message sent
prematurly.
Anyway, I rechecked
the wires to the EM2 and at the sensor again and all checked fine.
Again, I started the engine, but was shut down as soon as I still saw no
pressure.
Next, I hooked up two
separate mechanical pressure gages in three different locations in the oil
system, started the engine three times very briefly. Each time
the engin started and seemed to run fine for the VERY short time I allowed
it to run. No pressure reading on two of the test points, and
about 6psi on the reading from the turbor engine outlet to the
turbo.
Ok, I unscrewed the
oil filter, which is located remotely just as the oil comes out of the front (by
the pully's oposite the prop) of the engine. I hooked up a
remote start switch, climbed under the engine and cranked the engie.....I got a
moderate, steady flow of oil
From: Rotary motors in aircraft
[flyrotary@lancaironline.net] on behalf of Chris
Barber [cbarber@texasattorney.net] Sent: Tuesday, September 28, 2010 9:42
PM To: Rotary motors in aircraft Subject: [FlyRotary] Oil Pressure
Loss
In the never ending
tradition of two step forward and three steps back, I was working on my RPM drop
out at 6000 rmp (messed with seveal resistors to no avail). As I
was sitting on the ramp at idle for a few minutes, focusing on
the RPM's I glanced over at the Oil Pressure and noted it was flashing as
an alert and was showing almost NO oil pressure (4 or 5 psi). I instantly
shut down the engine.
The engine appeared
to be running fine before I shut it down. I checked the wire to the back
of the engine monitor and all was fine. I also checked the continutiy
of the wire to the sensor and it was good. I started the engine again and
it started fine and seem to run fine, however, the OP did not kick in so I shut
it down again
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