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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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