Oil Pressure Sender

The oil pressure sender I ordered from Lockwood Aviation arrived this afternoon.  I went to the airport to install it on the RV-12.  When I got there I cut the wire to the existing Honeywell sensor/sender.  I stripped the end of the wires and pushed them through the new cable attachment.  There are 3 wires in the oil pressure sensor cable but only 2-wires are used.  The red and white wires.  I cut the black wire short and put some heat shrink over the end of the cable.  After installing the connector I used the heat gun to shrink the wrap. 

I installed the sensor in the Adel clamp, plugged the newly installed connector to the sensor and fired up the SkyView.  No Joy!  I checked the continuity of the wires from the original connector to the control module.  Both the red and white wires were good.  I checked the continuity from the connector to the new pressure sensor and found no connectivity in the red wire.  In fact when I held the original spade connectors in my hand the red wire fell free from the female spade connector.  I striped the wire and crimped on a new female spade connector and the problem was solved.  I pulled the airplane out to the apron and started the engine.  The oil pressure immediately came to 58 psi.  As the engine warmed it dropped a few pounds but I am sure that has to do with the increased viscosity of the oil as the engine warmed up.  I ran the RPMs to 4,000 and the oil pressure remained constant.  I believe the jumpy oil pressure readings are now solved.  While waiting for an answer from Dynon I will return to the airport tomorrow and use my multi-meter to check the continuity of the servo wiring from the Control Module to the roll servo location.

Roll Servo

I removed the sevo from the mounting bracket in the tail cone.  After looking at the wires and connectors again I removed the servo from the airplane. 

I also removed the seat area inspection cover to expose the pitch servo which is located under the pilot seat.  Since the day I started flying the airplane I have had a caution message which reads “STANDYBY NETWORK ERROR.”  I have researched it several times and decided since it is a caution concerning a secondary communications back-up for the servos I could fly without it.  In researching the servo wiring  I found a statement that I must have read and understood incorrectly when I installed the servo wiring.  There are 2-wires on each servo that are to be left disconnected if the system is a D180.  My system is the SkyView D1000.  The wires should have been connected from the beginning.  Since they are called out as xxxx-a and xxxx-b at the control module I began to think they may be part of the STANDBY NETWORK ERROR problem I am experiencing.  I connected the wires at the pitch servo and switched on the SkyView.  To my great relief, the STANDBY NETWORK ERROR message did not come on.  I think that problem is now understood and solved.  I reinstalled the seat inspection cover and the carpeting.  I turned my attention to the roll servo.  After removing the servo from the airplane I took it to UPS and had them send it to Dynon Avionics.  It is to be delivered to Dynon on Friday the 29^th.  I emailed Dynon Tech Support the following message:

I have an RV-12 with the SkyView system.  I removed the servo today and shipped it to your facility by UPS ground.  It is to be delivered on Friday, August 29^th.  I believe the servo is bad because:

1.      In the RV-12 the roll servo is wired through the pitch servo.  The pitch servo is working properly.

2.       I checked all of the connections on both servos and the spade connectors are all properly seated and the crimps are solid.

3.       I have 12.+V power at the roll servo.

I appreciate your assistance with this issue. Please let me know your findings as soon as you are able. 

I received an email back from Steve at Dynon Tech Support thanking me of the information.  Steve  said he would add it to the work order.  

Roll Servo Error

Today I called Lockwood Aviation to let them know I did an oil pressure test with a mechanical gauge and the oil pressure is good.  The electronic sensor no longer registers on the SkyView.  Lockwood is going to send a new Honeywell replacement kit.  I should have it by the end of the day on Thursday the 28^th.  After that I returned to the airport to see if I could make any progress towards the Roll Error message on the SkyView.   Over the last couple of flights I have had  a ROLL ERROR message on the SkyView screen.  The roll servo is not coming on.  I emailed Dynon Tech Support and told them what has happened.  That the servo was intermittently coming on but as of now it won’t come on at all.  A tech responded by telling me to contact them on Monday the 25^th to make arrangements for a “Cross Ship” servo replacement.  I called Monday morning and the tech I spoke to suggested I do some checking to see if it is a wiring problem.  I started by disconnecting and removing the oil pressure test equipment.  I also called Dynon to report to them that I had the red X through the oil pressure gauge on the SkyView screen and to let them know I have ordered a new oil pressure sensor from Lockwood Aviation.  I was told I did the right thing.  I asked if the red X could be the result of the sensor going bad.  The tech said it means the values being sent by the oil pressure sensor do not register with the SkyView.  What kind of answer is that? 

Anyway, I removed the fuselage upper skin and the baggage area bulkhead.  I also removed the seats and rear carpet and upholstery. 

I climbed into the baggage area where I had access to the roll servo.  I checked the power to the servo and discovered there is 12.+ volts power to the servo.  I also looked at and pulled on the connectors.  All seem to be in order.  I also pulled the sub-d connector at the AV5000 and all of the connectors seem to be in place there also.  I called Dynon and spoke with Mike, the tech that said I should check the wiring and not just assume the servo is bad.  I told him what I have done and he is going to email me an RMA# (return materials authorization #) so I can return the servo to be checked.  This is a little different than I anticipated, but at least maybe I am going to get a solution to my servo problem.

Continued Oil Pressure Problems and Muffler Shroud

This morning I went to 3D Sheet Metal and had my good friend Sterling Smith (CEO) roll a shroud (shield) for the front of the muffler.  I had Sterling roll a 14” long half-pipe (6” diameter) to be installed on the front of the muffler between the muffler and the oil cooler.  I cut out the top 2-corners and drilled a series of holes in 2-rows.  The holes are to allow some air to flow through the shield and provide cooling for the muffler.

I then installed 2-pipe clamps with 3-3/8” machine screws to hold the shield close to ¼” off of the face of the muffler.  I put it in place and tightened the clamps.  I must admit I am pleased with the way it turned out.  I think this will be a good solution to my high oil temps on hot days.  I put the cowlings back on the nose and pulled the airplane out to fly it in the pattern.  I thought I could go up and do a few touch-and goes.  As soon as I started the engine I knew I was in trouble.  The oil pressure was all over the place.  Very unlike it was the day I moved the oil pressure sensor to the firewall.  It seemed to settle down as I let the oil temperature come up.  I taxied out to the run-up area and as soon as I advanced the throttle to 4,000 RPM all hell broke loose.  The oil pressure went from 8 psi to 65 psi and everyplace in between.  The SkyView begin annunciating an oil pressure warning each time it dropped into the red.  As I throttled back it seemed to settle down a little bit, but not much.  When I throttle up again the same thing happened. 

I decided to return to the hanger and remove the top cowling to see if there was a leak somewhere.  Upon removing the cowling I could see everything was fine.  No leaks and all connections were good.  I restarted the engine.  No change – just jumpy oil pressure readings.  I shut it down and moved the airplane back into the hangar.  I returned home and called Lockwood Aviation. I spoke to a tech named Mike. I told him I thought I have a bad oil pressure sensor.  I told him all of the problems I have had and the attempted relocation of the sensor as a solution.  He said it is very likely the oil pressure sensor has gone bad, but he told me before I purchase a new one I should install a mechanical oil pressure gauge and make sure the sensor is wrong.  I told him I would do so.  I went to O’Reily Auto Parts and purchased an oil pressure gauge.  I went to Lowe’s and purchased a tee and some fittings to install the gauge in the oil pressure line.  I put the contraption together and pulled the airplane out and started the engine.

This time there was a big red X through the oil pressure gauge on the SkyView screen.  However, the oil pressure on the mechanical gauge was rock solid at 60 psi.  I shut the engine down and checked the fittings.  All seemed to be good. I decided to re-crimp the spade connectors in the electrical system.  I re-crimped the 4-connectors, 2-on the sensor wire and 2-on the wire from the instrument area.  I restarted the engine and the same condition existed.  No oil pressure on the SkyView, but the oil pressure on the mechanical gauge continued to be rock solid.  I waited for the oil temperature to rise and then advanced the throttle to 4,000 RPMs.  The oil pressure gauge continued to hold at 60 psi.  There were small fluctuations when I would throttle back or advance the throttle but the pressure would quickly return to 60 psi and stay there.  I guess I will need a new oil pressure sensor.  I will call Lockwood in the morning and buy the Honeywell oil pressure sensor kit.  I hope this will be the solution.

Oil Change and Pressure Sensor Relocation

Today I went to the hangar and Cory Bagley was working down at John McDonald’s hangar.  Dennis King was also working on his Grumman Cheetah next door.  Cory came down to help Dennis for a moment and asked if I still needed some help with the oil change and inspection.  It was over 2-weeks ago that I called him and asked for his assistance.  He told me then it would be about a week before he would be available.  I said ‘yes I do’.  He said he was going to lunch and would come and help me when he got back.  I told him I would remove the cowlings and get things ready.  I proceeded to remove the cowlings and bought an oil collection pan at Auto Zone.  When Cory got back we started to change the oil and make the 25 hour inspection.

All went well.  Cory did most of the work.  I had all of the tools and supplies he needed including the oil, crush gasket, filter, safety wire, etc.  After the change he went down the Rotax 5.1) Maintenance Schedule check list and initialed all applicable boxes.  He also maked and signed an entry in the Engine Log Book.  I thanked him and will send him a check this weekend to pay for his services.  

I then proceeded to install the remote oil pressure sensor kit I purchased from CPC.  I started by removing the oil pressure sensor from the engine block and cut the wires loose from the various places I had tied it to hoses.  I pulled the senor back through the engine area so it was on the firewall shelf near the fuel pressure sensor.  I was able to do that little trick with no problems.  It was a challenge to cut some of the cable ties but I got to all of them.  I replaced the cable ties I removed to reattach the other wires that were tied in place. 

 

I installed the fitting on the engine block and attached the hose supplied with the kit.  I ran the hose over the top of the engine cooling shroud and back to the firewall shelf to near the pressure sensor. 

I cut  a small piece of ¾ x ¾ aluminum angle and drilled it for some 1/8^th inch rivets and the Adel clamp.  I riveted the angle in place and attached the  oil hose to the sensor then attached the sensor to the angle with the Adel clamp.  I cable tied the wires and hose in place.  I pulled the airplane out of the hangar and started the engine.  The oil pressure came up and was rock solid.  After shutting down I checked for leaks or other problems and found none.  I hope this is going t be the solution to my jumpy oil pressure readings of late.

Oil Pressure and Fuel Pressure Anomalies

The last time I went flying the fuel pressure continued to be high.  It bounces between the yellow and red alert on the SkyView.  Also, the oil pressure began to jump around while I was flying.  I called Lockwood Aviation and they confirmed that moving the oil pressure sensor to the firewall usually corrects the problem.  I have ordered an 'RV-12 Oil Pressure Sensor Relocation Kit.'  I will install it when it arrives.  I also did considerable checking on the forum.  It appears I am not the only one to have high fuel pressure readings.  I called Dynon and we checked to make sure the software and set up were correct.  They are.  I purchased a low pressure fuel gauge from O’Reily Auto Parts and hooked it to the fuel pressure sensor line.  It reads the same as the Dynon.  Because of that I decided to mount my electric fuel pump switch on the instrument panel.  

I installed the switch in the power wire (red) to the fuel pump.  I cut a hole in the instrument panel and installed the switch.  I then purchased some ‘white print on black’ tape for my P-Touch Label Maker and printed a label for the switch.  Now when the fuel pressure gets too high I can turn off the electric fuel pump.

I also painted the inside of the fuel tank cap red.