2024 - 2025 Electrical/Instrumentation Modifications

Engine overhaul
Electronics/Electrical
Fuel System
Trim System
Fabric Recover

Item #6 from the Rebuild page:  The rear cockpit is a hodge-podge of instruments and radios mounted whereever they could be fitted with little regard to ergonomics or visual scan.  I don't know that I'll straighten it all out, but I have purchased and Electronics International CGR-30 to consolidate all the engine instrumentation.  



11/13/2024 - Well now she's looking kind of naked.  All the sides, top deck and belly skins are removed.  They will all need to be cleaned and repainted, but having them off will also give me much better access to the instrument panel, plumbing, and wiring as I change much of it.


12/7/2027 - Pearl Harbor Day - While I wait for a few minor parts for the engine, I started cleaning up the rear cockpit.  The first thing was to remove the instruments that will be replaced by the new engine monitor.  Several old instruments will come out of the panel, and the bottom subpanel that's between my knees will go away all together.  I'll still need the forward part of the subpanel for the radio and transponder, but the rest is being removed.


Lots of other changes as well.  The control stick heads will be replaced with new handles that will include integrated trim and PTT buttons.  The elevator trim control (the Red knob) at the lower left of the photo will be removed.  I may rearrange the switch panel on the right side as it is a bulky and inefficient layout.


This is the front cockpit.  There aren't going to be any major changes here.  The electronic tachometer at the right side of the panel is inaccurate, so the old mechanical tach from the rear seat will be moving to the front cockpit to replace it.  The engine monitor going in the rear panel will have the tachometer integrated as part of the monitor.  The pipes and hoses running along the right side of the cockpit are being removed as they are there for Mechanical Oil Pressure, Fuel Pressure and Manifold Pressure gauges.  Those will be replaced by electronic transducers mounted at the firewall and are integraded as part of the engine monitor.  The same is true for the wiring from the CHT and EGT gauges as they will also be integrated as a part of the engine monitor.


12/9/2024 - Here's all the stuff that came out of the rear cockpit so far.  The subpanel from between my knees is on the left.  Combination Oil Temp, Oil Pressure, Fuel Pressure gauge, Tachometer, Manifold pressure, Ammeter, Exhaust Gas Temperature, and dual Cylinder Heat Temperature gauges.  All of these work and have the thermocouples and all but the tach are up for grabs if you need something.  The electronic tach from the front cockpit will also be up for grabs.


12/11/2024 - Building a new switch panel.  This one was kind of neat with military type covers over the switches.  But the switch covers are largely unnecessary and the switches are so spread out down this panel that it takes too much room.  I don't like reaching back behind my elbow to reach switches.  I'll build a new cover for the panel and remount the switches in a much more compact design.


The panel that was under the plastic panel.  All the switches and breakers are still hooked up; just hanging below the panel.  I'll rearrange the wiring and switches when I get started mounting everything into the new panel.


I'm going to fabricate a new cover from carbon fiber.  This is a simple wet layup of two pieces of carbon fiber on a waxed countertop that I use for wet layups.  


The layup is covered with peel ply (dacron fabric), then some felt to absorb the excess resin, then vacuum bagged using a medical vacuum pump and cheap painters masking plastic stuck to the board with the cheapest caulking I could buy.  It's cold in the hangar (roughly 55° F), so that's my oil filled mini-heater set to blow onto the layup overnight.  It is set on low heat and is also thermostatically controlled.  Additionally, the warm exhaust from the cooling fan on the vacuum pump is also blowing across the layup.  Even using West System Epoxy with the medium temp hardener for the layup and a bit of heat, it will probably still take at least a couple of days to cure.  Before someone tells me I'm not supposed to do layups this cold, it should be noted that this is NOT a structural layup.  If it was, I would not be doing this in the cold hangar.


Carbon fiber piece out of the vacuum bag and ready to be trimmed.  This will be a direct replacement for the panel above with a different arrangement for the switches and breakers.


12/13/2024 - I created a new panel template, used it as a layout on the old swiss cheese aluminum panel (see next photo) that was under the plastic switch panel.  Then I transferred the same hole pattern to the new carbon fiber panel.





New CF panel in place over the swiss cheese panel.  The old switch guards will be removed and most of the breakers will be replaces with more compact breakers that I have on hand.


New pieces in the instrument panel so far.  The white gauge on the left lower part of the panel is the fuel gauge.  Hopefully this one will actually function in flight.  The blank instrument towards the lower right is the Electronics International, CGR-30P.  This is an all in one LED display engine monitor.  I have this installed in the RV and really like it.  It offers a lot more than I really need in this plane, but also allows me to consolidate a bunch of engine instruments into one gauge that displays a bunch of data, but also triggers both amber and red warning lights if something gets out of spec with the engine.


12/12/2024 - Today was mostly about fabricating new hoses for the fuel system.  This is a photo of the mandrel in use driving the inner part of the fitting into the steel braid hose.  Yes, the hose is contains a steel braid and with neoprene on the inside, another layer or neoprene outside of the steel braid, then a cotton braided outer cover.  It is very stiff, but flexible.  These hoses needed to be made up to do the additional routing of the fuel system to include the fuel flow transducer.


All the hoses with blue firesleeve are new.  Starting at the lower corner of the photo, the hose runs from the fuel shutoff valve to the electric fuel pump.  Next to the electric fuel pump is the gascolator (water separator and fuel screen).  From the gascolator there is an orange firesleeve hose that runs to the mechanical fuel pump.  The output of the mechanical fuel pump runs up to the red block hiding behind the engine mount that is the fuel flow transducer.  From the fuel flow transducer, the line runs down to the carburetor fuel inlet underneath the engine.


These transducers also get installed.  The PT-100 is the Oil Pressure transducer, The PT-30 is for fuel pressure, and the red block is the fuel flow transducer.  The gold colored transducer below is the manifold pressure transducer.




I mounted the oil and fuel pressure transducers to the firewall (left), the manifold pressure transducer (right), the fuel flow transducer (the red block) and the EI data module (top center) to the firewall.  I had some of these mounted yesterday, then it occured to me this morning that once the plane is back together, the nuts on the back side of the firewall will  not be accessible.  So, I spent the morning riveting nutplates into the firewall.   All these transducers feed data to the EI CGR-30R engine monitor display.


12/16/2024 - Today was about connecting and tidying up the wiring for the engine monitor.  All the brown wiring in the photos above and below is Thermocouple wiring.  4 EGTs, 4 CHTs, Oil Temp, Outside Air Temp, and Carb Inlet Temp.  There are a couple of white wire buncdles just behind the master relay on the near side of the firewall that go to the Fuel Flow Transducer and Manifold Pressure Transducer.  In the photo below, you can see two black wire bundles that are zip tied to the top of the firewall/engine mount that go to the Oil Pressure and Fuel Pressure transducers.


I took advantage of existing holes in the firewall that used to house pressure lines that are no longer needed to route excess wiring behind the firewall where it is bundled, then enough wire pulled back through the firewall to route around the engine as necessary.  There is still more wiring to pull, splice and mount for the engine monitor, but this is the bulk of it.  I do still need to pull a data line from the data module to the display, and another line to monitor the voltage.  I need to find a place to install the shunt for the ammeter and pull the wiring to the shunt.  There is a bunch more wiring work to do that I'm not quite ready for yet, so there's still more to come on that.


This is the carbon fiber switch panel I fabricated.  There are 7 switches and 5 breakers.  In order the switches are Master, Starter, Aux Fuel Pump, Avionics, ADSB/GPS/USB ports, Nav Lights, & Strobes.  I rearranged the layout and order of the switches, so all the wiring below the switch panel is cut loose.  Some wiring will need to be added and some other wiring replaced.  When completed, it will all get zipped up tightly in place.  I broke the USB port for my GPS while pulling the wiring from it, so had to order a replacement.  It won't be in until this weekend.


12/17/2024 - Not much to show photo wise today.  I have all the switches and breakers in the right side console now.  I still need to tidy up the wiring a bit under the console and replaced the USB port that I broke, otherwise it's done.


Small change to the front panel.  Again, not much to show, but took hours of fiddling around.  The electric tach that was in the right side of the cockpit was removed and the mechanical tach from the back panel was to be installed.  Then I had a small interference problem where the angle drive on the back of the tachometer was going to rub on one of the center section braces.  No problem, I'll just swap it with the airspeed indicator.  Easier said than done.  Now I had some challenges with whether the new tach cable would reach.  It did with some different cable routing.  Then the pitot and static lines to the back of the Airspeed Indicator didn't reach.  I found that I had all the right stuff on hand to extend or replace the lines as needed to make everything fit.  But it took a lot of fussing around and searching through my parts bins to get it done.


12/18/2024 - Today I completed the switch and breaker mods to the side panel and tidied up all the wiring.  Below you can see the CGR-30R Engine Monitor from Electronics International is finally lit up.  The 3-1/8" hole to the right with a square hole in the filler panel is cut to fit the trim indicators.  I'll be redesigning the trim system and adding servo controlled trim tabs to the tail next.


12/24/2024 -Christmas Eve...   Today's goal was to wire in the switches for the new stick grips.  The switches on the stick control elevator trim, radio transmit, and intercom transmit and all are active from either seat.  I decided to add a terminal block under the  right rear floorboard along with the relay deck for the trim servos that came with the stick grips to enable the trim servos to be controlled from either seat.  You can see the relay deck just under the wiring connected to the terminal block.  I still need to pull a ground wire, +12V wire, and the two servo leads to complete this part of the installation.  I also need to wire in the trim indicators in the instrument panel.  I failed to take a photo, but today I also fabricated a new panel mount for the trim indicators and painted it black.  It will show up in the next round of wiring when I install the indicators.  I'm waiting for some mini-Molex connectors to arrive to complete the connections, although I can pull the wiring to the tail yet.  The connectors should arrive on Saturday.




12/26/2024 - The trim indicators are temporarily mounted in the left side of the panel.  I just need to replace the clecos with screws.


The terminal block under the floorboard is completed.


I'm waiting for crimp on ferrels for 24 gauge wire connectors and mini-Molex connectors so I can complete the wiring for the elevator trim servos.  This stuff should all be here this weekend.


I started stripping the fabric from the aft fuselage so I could route and attach the wiring for the elevator trim.


12/29/2024 -  The connectors I've been waiting on arrived in yesterdays mail, so I've now completed all but the installation of the fuel tank sending unit for the electrical/electronics work to be done on the plane.  Now I have the trim indicators mounted and lit up on the right side of the panel.  Compare this cockpit photo of the finished rear cockpit to the photo below from before I started.


Also compart the switch/breaker panel on the right console to the finished panel below.