I didn’t do too much actual work on the plane today. I mainly did some research to understand the different sensors and what is needed. I did make the mount bracket for my fuel pumps, and alodined a few parts. Additionally I tightened down a few bolts of the alternator bracket that I figured wouldn’t need to be removed. I left the bolts on the arm loose since I will have to tighten the belt on the alternator and can’t do that just yet. I also found that my oil thermostat doesn’t have metric threads even though the firewall forward manual calls for 6mm (12mm long) bolts they’re actually 1/4-20 bolts. 6mm and 1/4 are very close and the 6mm bolt threads in a little, but the threading is different. Fortunately I had a few bolts lying around so I was able to find one that fit and now I just have to order them from Bolt Depot.
What I mainly did today was look through the Garmin and Rotax manuals to figure out the sensors that I need to get. The newer Rotax engines are referred to as “Suffix -01” this is because they have a -01 at the end of their model numbers, for example mine is a 914ul2-01. The reasoning was because Rotax made a change to the cylinder heads to make all the parts the same. So with that there are no longer cylinder heat temperature sensors on the bottom of the cylinder heads, rather there are now 2 coolant temperature sensors on the top. This caused some confusion for me since both are shown in the Rotax install manual. Garmin sells a Rotax kit for use with the GEA24, but there are a few things that you pay for that you don’t use on the 914 and you still need to purchase a few other sensors so I’m thinking I may just skip it and get everything separate. I have detailed my findings in the following table.
|Coolant Temperature||Rotax 965531||Supplied with engine (Located on cylinder #2&3).||Use shielded 2 conductor wire 22AWG cabling terminate with 250 Faston and ring terminal (for ground) onnector|
|Coolant Pressure||KAVLICO P4055-50G-E4A||Saw this mentioned in Garmin manual, but not sure if it’s applicable to the 914, may be 912IS only||Use 3 wire 22AWG shielded cabling|
|Oil Temperature||Rotax 965531||Supplied with engine (Located on oil pump).||Use shielded 2 conductor wire 22AWG cabling terminate with 250 Faston and ring terminal (for ground) connector|
|Oil Pressure||Rotax 456180||Supplied with engine (Located on oil pump).||Use supplied cable and connector. Wiring is long enough to reach GEA24|
|Mechanical Rev||Rotax ?||Supplied with engine (Located on generator).||Use pins 26&11 from TCU along with zener diode, diode, and 300ohm resistor (comes with Garmin kit or source yourself)|
|Manifold Pressure||KAVLICO P4055-30A-E4A or P500-30A-E4A||Can’t find this sensor, Also may be available from Dynon. Comes in the Garmin Rotax 912/914 kit.||Use 3 wire 22AWG shielded cabling|
|Airbox Temperature||VDO 323057||This is not required, but will try this sensor. Sourced from Amazon and looks like it should fit (1/8 NPT -27 threads).||Use shielded 2 conductor wire 22AWG cabling terminate with 250 Faston and ring terminal (for ground) connector|
|Fuel Flow||FT-60||Aircraft Spruce has these (part # 10-01196)||Use 3 wire 22AWG shielded cabling|
|Fuel Pressure||UMA N1EU07D||Aircraft Spruce has these (part #10-00980)||Use 3 wire 22AWG shielded cabling|
|EGT||TYPE K TERMOCOUPLERS||Aircraft Spruce has these (part #15-09438). They can be ordered with 6 or 9 foot wires so no need to buy special K type wire. Also should mount to M8 threads in exhaust.||Use supplied wire|