Jim Price’s comment had just hit bullseye, one I didn’t even know existed.
I tried explaining that for redundancy’s sake I had both a mechanical and an electronic oil pressure gauge, deep down knowing that that wasn't even a mediocre answer to his probing question.
“You know,” he continued “In thirty years I have lost oil pressure three times, and knowing exactly when that happened allowed me to reduce power, look for a place to land, and save the engine... and myself.”
Had we been playing Battleship, my Aircraft Carrier would have been on its way to the bottom of the ocean.
Jim’s wise words perturbed me that night. He had probed my defenses only to find my shields running at 50% power. Something would have to be done about this, in the morning.
Truth be told, I have always had a hard time keeping my oil pressure gauges within my scan, and had one of Jim’s oil leaks sprung on me, it is very likely that the first indication of a problem would have been a seized engine, and a mad scramble for some flat pavement.
In a situation like this, where every second counts, getting a couple of minutes heads up on the impending doom might just spell the difference between a good outcome, and a not so good one. All of a sudden the power of a $10 idiot light, especially when combined with an actual oil pressure gauge, could no longer be ignored.
Ideally the red light would immediately compel my attention, and alert to a low oil pressure scenario. The gauges could then be referenced to verify the condition. Reducing engine power immediately might just prevent the engine from tearing itself apart long enough for a safe landing to be accomplished ASAP.
I knew I had to have one.
More sophisticated glass panels already have digital versions of both gauge and light built into their software, but my GRT Minis have no connections to the engine, so an independent analog system is required.
I had two mounting options, either put the oil pressure sensor behind the firewall, and run wires all the way up to the instrument panel light, or tie into the existing oil line that already ran to the panel to power the mechanical oil pressure indicator, and just string a much shorter wire to the new light.
This latter option was more appealing because it saved a little weight, and also moved it forward, where it is less detrimental to JT’s Center of Gravity. Didn’t hurt that it was a somewhat simpler installation as well.
Of course I immediately ran into problems. Turned out I purchased a gauge that was designed to ground itself through a metal instrument panel, but mine is non conductive fiberglass. I should have gotten one with a separate ground lead, but I didn’t know any better when I ordered it, so now I had to start modifying the modification 🤯.
To make a long story short, I made a washer with a tab out of leftover steel, and connected a wire from the tab to the nearby ground bus.
Problem solved, right?!
Not so fast!
First I had to repurpose a ⅜”-24TPI nut, turning into a NPT tapered thread, so that it could secure the special washer onto the brass splitter.
About the time I thought I had just solved this problem, I realized that my current oil pressure gauge had an additional appendix that would not allow me to screw the brass piece on without running into it.
Luckily this surgery was performed under local anesthesia, and I was able start trial fitting right away.
In the end this mod was neither too difficult, expensive, or much of a weight penalty not to install. It has performed flawlessly so far, as one would have expected, and I’m actually growing fond of the little thing.
It is always the first thing I look at after engine start. I do stare at it for the few seconds it takes the oil pressure to raise above 20 psi, when the light promptly goes out letting me know all is well. I then quickly verify the actual pressure readings on the two gauges, and continue on with the rest of the checklist.
Thank goodness for wise Jim!
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