Published on May 25th, 2015 | by FII Reader0
I learned about flying from that
Beware of the Dipstick!
Some jobs are too important to delegate!
Jabiru 2200a Oil Level Dipsticks – What could go wrong?
Good mechanical reasons and evolving engine changes over the years have prompted Jabiru to change the size and shape of the oil sumps of their 2200 and 3300 engines. The graphic below shows how Jabiru changed the dipstick lengths to accommodate the varying sump depths. All very clear and simple so far?
As befits its status in life, a Jabiru dipstick just sits there most of the time and minds its own business. Dipsticks are humble creatures that rarely do anything to seek or create publicity. Granted, there was great dipstick “knurled nut” controversy of 2012; highlighted by the BMAA in a bulletin (READ IT HERE). Jabiru nipped that little insurrection in the bud before the dipsticks could generate real publicity and get ideas above their station.
But recent events at our club show that you can never trust a dipstick. Bored out of its tiny brain by hours of just sitting there, the highlight of a dipstick’s life is to be unscrewed and breathe some fresh air, or better still to feel the balm of freshly poured oil. That’s when the rabid dipstick is mostly likely to strike. If you’ve ever fed a bored and hungry dog you’ll know what I mean. Watch out!
Even the slightest inattention to detail by your superhero pilot in command (PIC) can unleash the frustrated ferocity of the dipstick. Too much oil and the dipstick will spit it into the breather bottle with contempt. Too little oil, and you can hear the dipstick hissing and sneering as the sweating PIC watches the oil temperature rise inexorably.
All keepers of dipsticks and bears know that the greatest sin of all is not to close the cage properly. Finger tight is good enough to keep the dipstick locked in position. Finger loose, isn’t! It may have a feeble brain, but the dipstick will never pass an opportunity to cause havoc! Thread by thread it effects its revenge for those eternal hours of boredom. Then, with one hot slurp, comes the frenzy of dipstick revenge! Hot sump oil is dumped overboard in the shortest time and with the maximum trouble for the PIC.
It could never happen here, could it? Last week a dutiful PIC checked the oil level on one of our club aeroplanes for the first flight of the day. Guess what he found? The dipstick was held on by only two thread turns. The PIC from the day before had taken the previous PIC’s word for it that the ‘oil was ok’. Haven’t we all done it?
Imagine you are sitting in the cruise and hot gunk starts to cover the windscreen as the engine parameters go red. You’ll know immediately what’s wrong and why. Then you’ll recall the real meaning of the word dipstick: an unintelligent person; “idiot”; “moron”.