Shade tree mechanic strikes again
- Thread starter Ed Haywood
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I still use koroseal lacing. When done well, it will last a long time and not create other issues.
Something that gets overlooked often is the fact that maintainers are supposed to be ensuring compliance to standards, not changing a design to suit immediate needs.
Something that gets overlooked often is the fact that maintainers are supposed to be ensuring compliance to standards, not changing a design to suit immediate needs.
texasclouds
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Well, my cowl was off for oil change. I found a metal clamp (non rubber lined) holding my carb heat cable to the tubing. My mixture cable was zip tied to the tubing with some split fuel hose in-between. Also some loose adel clamps. Minor scuffing but no damage.
My new mechanic helped me fix it up properly. Thanks for the heads up.
My new mechanic helped me fix it up properly. Thanks for the heads up.
Except most adels have a cushion that separates the adel band from the parent tube and when installed properly are not the same regardless the width of the adel. However, if an adel is improperly installed, even with the cushion material it can also cut into the parent tube when the right circumstances exist. Cable ties have no cushion material. Helicopters are ten-fold more susceptible to this type damage but have found a number of airplanes with similar damage due to the same mechanism. As I stated earlier, cable ties have no place in engine compartments or other exterior locations. However, its one of those things, believe me now or pay me later to fix it. Easy money for me.
I wondered about this myself. I just had my engine mount overhauled and painted at AWI (They purchased Kosola) in Minnesota. I called yesterday to ask about this old wives tale. He told me to remove any zip ties from the mount. I had three with the rubber hose stand off on a lower tube holding some wires and I'll be replacing those with adel clamps in the very near future. YMMV.
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just passing through
But I suspect that the result wont be a PSA of "See what years of neglect cause?" but rather a slew of ADs that will cause the cost of ownership to go up for those who do properly maintain their aircraft in the first place.
Capt. Geoffrey Thorpe
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Light and Sporty Guy
Not me. My chain fall is hanging from the rafters in the hangar. Handy for pulling a wing single handed. (Engine comes off with a cherry picker).
I love the saying "cherry picker" we call it that also sometimes. Wonder where it came from?
Pinecone
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I was going by what YOU said. That a single speed pump was replaced with a multispeed pump.
But again, this is the type of thing the A&P should know/evaluate.
Checkout_my_Six
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With all these shade trees....we still have a shortage of mechanics. 
It's because we stay hidden behind closed hangar doors...With all these shade trees....we still have a shortage of mechanics.
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Fortunately/unfortunately, quite a few aircraft can "handle" abuse and lack of proper mx for years. Just like the pics in the OP. What you are starting to see more in recent times is when there is an accident/incident there has been more focus on the maintenance side. There was a recent thread on PoA of an accident where the NTSB prelim noted "rust" on the interior engine surfaces. Without context it was unknown if it was missed during the recent mx or if it was there prior to flight. However, most here thought it was the mechanics fault for missing it. Or was it like the OP owner above who allowed it? What's changed is there are an increasing number of aircraft like the OP pics above than there used to be. Will it lead to more ADs, who knows. But it will lead to more legit mechanics refusing to work on aircraft based on condition alone while unfortunately keeping the not so legit mechanics gainfully employed. Thankfully I no longer need to play this game.
How can a mechanic see rust on the interior (inside) surfaces of an engine during normal maintenance? I am thinking about the notorious Lycoming camshafts that get rusty. Not even X-Ray vision can see that. Pulling cylinders off to look for rust on the camshaft is not routine.
Dan Thomas
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The pumps were always "single-speed" pumps, with their RPM varied by resistors in its power circuitry. What is it about this that you don't get? DO I have to post the wiring diagram, with the date it was drawn? NOTHING was changed except the pump itself, and that new pump had a lower current draw, which fouled up the voltage drops at the resistors. Ohm's Law. Look it up. Those old resistors had to be replaced with new, higher-resistance units to get the voltage drops required.
A&Ps should know Ohm's Law, but I found that the weakest area in all of aircraft maintenance is electrical troubleshooting. It results in the mechanic throwing parts at the problem until it goes away. If I worked like that I would have replaced the pump four times until it dawned on me that we had some other problem.
Dan Thomas
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Proper operation will avoid those corrosion issues in the engine. Don't ground-run it. Don't fly for just 20 minutes. There is a wealth of advice on this subject elsewhere, but pilots really don't care to read the stuff and learn from it.
I totally agree, but does a mechanic do a thorough interview with all owners and previous owners asking them how they operated their airplane the entire life of the engine?
Dan Thomas
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The mechanic finds rust in the oil filter. He finds the compression down due to cylinder pitting. If the cam or lifters are spalling he sees steel flakes in the filter. If he finds aluminum chips in the filter he suspects piston pin plugs being chipped by the ridge left by the bottom piston rings in a corroded cylinder. If he takes a magneto off for any reason he sees rusty gears in the accessory case.
Plenty to see without pulling a cylinder.
Checkout_my_Six
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Yup....and a shade tree mechanic would never find that. Cause he's in the shade.
The implication was by most the mechanic should have seen it as that is their job.
Short answer is yes, some of us mechanics interview owners and their practices prior to accepting them as a client. The interview may not be specifically about engine operation but it is intended to weed out the owners that will be nothing but trouble. Based on posts I’ve seen on this board, there are likely owners here that I wouldn’t work with.
What about those out there (mechanic, owner, pilot, joe blow) who don't know what they don't know? Blissfully blasting along, feeling fat dumb and happy, doing what they think is right.
Owners are legally responsible for their aircraft's condition. Some take that seriously. Some take that as a necessary evil, to be done as quick and cheap as possible. Some mechanics are willing to bend more than others to keep the owner happy.
Well, a pitted cylinder can still have perfect compression readings because differential compression is done at TDC. It doesn't catch pitting that is lower down the cylinder. Same way a compression test wouldn't catch a cam lobe problem because the valves are closed at TDC. I owned an airplane with a O360 Lycoming. There were times that it sat in the hangar. I did oil analysis every other oil change. Cut open oil filters, and boroscoped cylinders. There was no indication of anything alarming. When the engine was disassembled for overhaul, there was staining on the cam lobes and lifter bodies indicating previous corrosion, and there was light rust on the non-polished areas of the cam. I imagine that this would have been considered "found rust on the interior surfaces of the engine".
I can see it now. FAA mandating an annual inspection application in the likes of MedExpress. Question 1: Has the airplane "ever" been non-operated for 3 months or longer without being preserved? For an affirmative answer, mechanic must submit all documents proving there is no interior rust. Help us if it ever gets to that. But I sure wouldn't say never.
I have seen Feds “ lean on” folks to have a log entry for times their aircraft is out of Annual. So if you had a period of something like 3 months between the expired Annual and the new Annual the owner should state in the log that the aircraft was not flown .
I think it was an individual harassment type of action.
I think it was an individual harassment type of action.
Sounds like they are just fishing for people who flew their airplanes out of annual. I wouldn't be surprised if they asked to see the pilot log too. Otherwise, anybody can see the annual dates on the logbook and know when there were periods it was out. Not rocket science.
schmookeeg
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Checkout_my_Six
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I got news for the AFS guys here.....DC won't be tightening these regs until the accident rates due to maintenance goes up. And that ain't happening....not even with experimentals....and they require nothing but owning the aircraft to turn a wrench.
In fact....or IMHO....if all y'all want to see things improve....allow more owner maintenance.
In fact....or IMHO....if all y'all want to see things improve....allow more owner maintenance.
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I agree about owner maintenance of experimentals, and don't forget about experimental light sport owners that can even do their own annual condition inspection after taking a 2 day course.
Would really like to see a similar option for all experimentals, even if it is a fair bit more than a 2 day course. Would not a more knowledgeable pilot make a safer pilot?
Doc Holliday
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The “owner maintenance” I’ve observed, done behind close doors with a bought signature, I wouldn’t dare get in the plane and go fly.
Aviation is expensive, and requires knowledgeable owners.
Trying to dumb down the system is not the answer.
Pinecone
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If the installation had more than one speed, how are they single speed?
Again, if you substitute, the A&P needs to determine that it is a like for like and that nothing else is changed. How hard is if for you to understand that?
In your case, there was more far reaching issues, that constituted a change in design (resistor values). But did you say that CESSNA made this change of part?
Checkout_my_Six
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Point is....they are already doing it. Why not give folks a way to learn and do it legitimately?
In my experience, the people doing those kind of activities don’t want to learn and They think they know it all already. Their handiwork is usually easy to spot.
Having an owner maintained category of aircraft might solve some of the problems, as it would indicate which ones to stay away from.
Doc Holliday
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Checkout_my_Six
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This usually doesn't bring a welcomed response.....cause A&Ps think this dips into their rice bowel. It really doesn't. They weren't gonna pay anyways to have you do the work.
Doc Holliday
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This usually doesn't bring a welcomed response.....cause A&Ps think this dips into their rice bowel. It really doesn't. They weren't gonna pay anyways to have you do the work.
That’s usually the canned response, which is far from the truth.
Typically what happens after several cheap owners an unsuspecting pilot buys this “cream puff”, and wanting to be responsible, takes the plane in for maintenance, only to find out that years have passed since it’s actually had any, but yet has a logbook full of sign offs.
New owner gets a huge estimate to bring it airworthy, freaks out and wants to blame “the greedy mechanic”.
Meanwhile, the signature sellers continue signing off airplanes for the cheap owners.
Salty
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So? Why do you care if an idiot calls you a greedy mechanic?
Doc Holliday
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Yep, that's been my experience as well.