Should I expect this problemn to be fixed

[eddyb123]

I have an electrical problemn. As I fly my amps discharge I lose my radio and then the A/C won't start again. I give it to the shop they come up with you need a new starter, new cables etc. I went for my first flight and I still have the same problemn. I know it's just the best guess sometimes but really should I expect the problemn to be fixed? 1962 Piper Cherokee 160

[cgzro]

Thats a symptom of an alternator or regulator not working, not starter. Did you tell your mechanic that the plane was hard to start, or that the battery was discharging in flight? Sounds like you just told him it was hard to start in which case he would have suspected the battery and/or starter/cables. You need to give your mechanic as much detail as possible to make sure he can diagnose the problem properly.

Anyway first thing I'd check if my battery was not charging would be the alternator/regulator fuse/circuit breaker. Then I'd look to see if the alternator fan belt was loose or missing. After that you can put a voltmeter on the battery after charging it to see if its holding its charge, or has a bad cell. Beyond that .. you need the mechanic to check the regulator/alternator and wiring.

Good luck,

Peter

[eddyb123]

I told them the the battery discharged several times. I would charge it and fly it and loose electrical. The gen would be the first thing I'd think of. Or I thought a new battery would be the simplest. I've spent $1000.00 x ? and still have the original prob.

[CpnCrunch]

Yeah, I would expect them to actually diagnose the problem first rather than just replacing bits and charging you $1000. Perhaps it's time to find a new AME . We just had a similar problem on our plane, but we diagnosed it ourselves so we knew exactly which bit needed replaced.

[Taiser]

How the hell can a "mechanic" link "my ammeter is showing a discharge" to the cables or the starter, without checking the output from the Alt first??? I'd be RUNNING not walking to a new mechanic!!! After I yelled at the first one first for wasting my money!!!

[CID]

Your mechanic sounds like a dud. I would force him to take his starter back for a full refund. Then I would find someone who didn't get their license out of a cereal box.

The electrical system on a Cherokee is about as simple as it gets! By the way, if you're showing a discharge in the air, that indicates a failure of the generating system. Why on earth would you continue to fly it?

[Colonel Sanders]

Not one word about poor diagnostic skills.

I'm sure I will be viciously attacked for saying this, but I
would never go to an AME with a vague complaint about
an aircraft.

Tell him: "replace voltage regulator" or "swap out cyl #3".

[eddyb123]

Thanks guys for your comments and opinions, if they don't help me then I hope others will get great ideas when having problemnswith their A/C. I do suffer from bad diagnostic skill syndrom and will make a real effort to get better.
Why would I keep flying it? Because my AME told me it was good to go multiple times. When the battery is charged the amp meter shows positive at run up, but I should have noticed a discharge after a few circuits and not let my radio fail, I always have a handheld as backup.
I talked to a great mechanic yesterday who helped me with the problemn. And again I'd like to thank you all.

[GyvAir]

Not one word about poor diagnostic skills.

I'm sure I will be viciously attacked for saying this, but I
would never go to an AME with a vague complaint about
an aircraft.

Tell him: "replace voltage regulator" or "swap out cyl #3".

I know you're just trolling here, but..

That's great for your personal situation, having a mechanical background and the ability to diagnose a problem with reasonable certainty. How many pilots are going to have what it takes to narrow the problem down a faulty voltage regulator and not the alternator/generator or one of the many wires or connectors in between?
I guess an AME would love being told so specifically what to do though. Makes billing a breeze.

[Colonel Sanders]

How many pilots are going to have what it takes to narrow the problem down

If a pilot/owner can't understand a simple 12VDC wiring
diagram, he's going to pay dearly for that lack of knowledge.

I was up recently, giving some dual to a pilot/owner and
his ammeter was showing a slight discharge. Didn't make
any difference if the field was powered or not. Hm. Increased
the load with the lights, needle deflected left and stayed
there, so the gauge was probably working, but the charging
system was not.

We landed, pulled the cowls - easy there, legal beagles,
that's elementary maintenance - and I was hoping it
was just a broken field wire to the alternator, but no
luck. Without any wiring diagrams at all, in a matter
of a couple minutes with a $20 voltmeter I had diagnosed
that the alternator had failed.

Sure enough, his AME pulled it later, it was all melted
inside.

If you can understand plumbing, you can understand
DC electrics, so you can tell your AME: "replace alternator".

PS Remember, whenever you change an alternator,
always always always re-charge the battery up again
before you start it! An alternator WILL NOT charge
a dead battery (but a generator will).

I can't possibly imagine flying an airplane without
understanding it's systems.

[GyvAir]

I'm pretty sure that even at the 172/Cherokee level you're going to find that the vast majority of pilots wouldn't have the ability to diagnose a charging problem even if you took the cowl off for them and handed them a meter and wiring diagram. For most people I know, a DMM is PFM. Sadly that even goes for a number of AMEs I've encountered over the years.

[KISS_MY_TCAS]

Pilots that troubleshoot, can be trouble. Colonel Sanders, while you may have a knowledge of aircraft and technical/troubleshooting skills that are valid, from my experience you are in a minority. I have had endless pilots and owners that have attempted troubleshooting systems without a working knowledge to justify their actions. They lead the AME astray, then get pissed when slapped with a bill for following a bad lead and not finding a problem, or following a bad lead and doubling their troubleshooting by eliminating a pilot theory before finding their own troubleshooting path. There are obviously problems afoot here by chasing a start circuit for a battery discharge, it is it possible that the AME was lead astray? If you do not understand a system completely when it causes issue, do not waste the AMEs time. Tell him/her what it did, and any other relevant info you can related to the incident but know your own limit of knowledge. If you lead an AME astray, you will get billed and you will be mad if it is not fixed, period. I have seen it countless times with private owners and commercial drivers alike, I can't fly it, and you can't fix it. If in fact you were honest with the shop and told them EXACTLY what you experienced with the airplane without an opinion on what you thought the problem was, indeed seek a new shop. Most AMEs can't stand genius owners that sidetrack them and then get mad about the billing for obvious reasons. I have humbled many a pilot after they attempted to "school me". Experienced AMEs/AMOs can sniff bullshit from a mile away and it will hit your wallet. Inexperienced AMEs/AMOs are a different argument. Hopefully you weren't bit by the latter.

[iflyforpie]

That's just it. Pretty easy to lead an eager junior mechanic astray with poor information or troubleshooting and it's pretty easy to get raped by a devious one. One former DOM of mine told me to replace a battery just before I told him the reason why the aircraft wasn't starting was the fuel selector was in the off position.

Usually when somebody comes to me with an electrical problem or any problem for that matter, I get them back up and tell me everything they can, and then we try and duplicate it. Start from easy to hard, cheap to expensive. First thing should be the battery being pulled, tested, serviced, and charged. This eliminates a whole pile of scenarios right off the bat. While it is charging, you can look at belts and drives, corroded terminals, possible shorts or opens. If the battery is weak, best to replace it because it might be contributing to other problems (working the alternator too hard, lack of protection from transients, etc).

I never replace an alternator without having it bench checked first. Just about every town has a car electric or a heavy duty shop that can run it on a bench since most are Ford or Chrysler anyways.

There is no way a starter can cause an electrical discharge without a ton of other problems first.

[Colonel Sanders]

I can't believe the problems people have with simple 12VDC
electrical charging systems in light aircraft.

You should try looking at systems with millions of lines of
source code and fine-grained locks. The race conditions
would boggle your mind.

[CID]

Suggesting that a pilot should to be able to direct an AME to the part that needs to be fixed is ludicrous. Why stop at that Colonel? Why don't you recap the tires and make your own bolts?

The DC generating system on a light piston IS quite simple but so what? Do you tell your doctor what medicine to prescribe?

[Bede]

Im with col.. This stuff isnt rocket science. Neither is flying for that matter. A pilot should be able to troubleshoot basic stuff on an airplane. I respect what AME's do but the "youre a pilot and dont know any thing" is annoying. My wife flies small stuff and when there was aproblem she knew how to fix it. When we changed AMO's the guys would give her a hard time untill the learned she knew what she was talking about.

[Colonel Sanders]

Suggesting that a pilot should to be able to direct an AME to the part that needs to be fixed is ludicrous

No, it isn't. And if the OP had taken my advice, he
wouldn't have had all those extra parts replaced by
his AME.

Light singles are really, really simple. If you look at
the list of legal elementary maintenance items in
CAR 625 App A:

http://www.tc.gc.ca/eng/civilaviation/r ... a-2458.htm

It makes it quite clear that a pilot/owner, if he so
desires, can get quite involved in his aircraft maintenance,
despite your desire that he does not:

Elementary Work Task Listings

(1) fabric patches measuring not more than 15 cm (6 in) in any direction and not requiring rib stitching or the removal of control surfaces or structural parts, on small privately operated aircraft;

(2) removal and replacement of tires, wheels, landing skids or skid shoes, not requiring separation of any hydraulic lines, on small privately operated aircraft;

(3) removal and replacement of skis on fixed landing gear, not requiring separation of any hydraulic lines, on small privately operated aircraft;

(4) repair of non-structural fairings, cover plates and cowlings, on small privately operated aircraft;

(5) cleaning and replacement of spark plugs, on small privately operated aircraft;

(6) checking of cylinder compression, on small privately operated aircraft;

(7) cleaning or changing of fuel, oil, and air filters, on small privately operated aircraft;

(8) draining and replenishing engine oil, on small privately operated aircraft;

(9) checking the electrolyte level and specific gravity of lead acid batteries, on small privately operated aircraft;

(10) adjustment of generator or alternator drive belt tension, on small privately operated aircraft;

(11) cleaning of balloon burner nozzles;

(12) removal and replacement of balloon baskets, burners and gas tanks that are designed for rapid change in service;

(13) removal and replacement of glider wings and tail surfaces that are designed for quick assembly;

(14) repair of upholstery, trim and cabin furnishings;

(15) removal and replacement of role equipment designed for rapid removal and replacement;

(16) removal and replacement of passenger seat belts and harnesses;

(17) removal and replacement of fuses, light bulbs and reflectors;

(18) removal and replacement of avionics components that are rack mounted or otherwise designed for rapid removal and replacement, where the work does not require testing other than an operational check;

(19) removal and replacement of aircraft batteries;

(20) removal and replacement of co-pilot control levers, wheels, pedals and pedal guard plates that are designed for rapid removal and replacement, on other than transport category aircraft;

(21) opening and closing of non-structural access panels;

(22) removal and replacement of cabin doors on unpressurized aircraft, where the door is designed for rapid removal and replacement;

(23) removal, replacement and repositioning of non structural partitions in the passenger cabin;

(24) inspection and continuity checking of self-sealing chip detectors;

(25) removal and replacement of induction system anti-icing baffles, scoops and deflectors that are designed for rapid removal and replacement;

(26) removal, cleaning, replacement and adjustment of external components of chemical dispersal systems that are designed for rapid removal and replacement;

(27) deactivating or securing inoperative systems in accordance with sections 605.09 or 605.10 of the CARs, including the installation of devices specifically intended for system deactivation, where the work does not involve disassembly, the installation of parts, or testing other than operational checks;

(28) checking and adjusting air pressure in helicopter floats and aircraft tires except on aircraft operated under CAR 705.

(29) repetitive visual inspections or operational checks (including inspections and tests required by airworthiness directives) not involving disassembly or the use of visual aids, performed out of phase with the aircraft’s scheduled check cycle at intervals of less than 100 hours air time, provided the tasks are also included in the most frequent scheduled maintenance check.

I guess it really bugs you that I helped out - again -
another student of mine as I described previously,
when he had a charging system failure. I rapidly
diagnosed the problem correctly, and saved him
from his AME changing parts by shotgun, as was
described by the OP in this thread.

Sometimes I despair that anyone can correctly
diagnose anything. Job security, I suppose.

You must admit that AME's have a spectacularly
poor record of diagnosing electrical problems. In
my experience they have a spectacularly poor
record of diagnosing any problem.

Doctors are only marginally better than AME's at
diagnosing problems, despite supposedly being
Really Bright Guys (tm) to get into medical school.

Like most AME's, most doctor's are fair at best at
diagnosing a problem. Like most AME's, most doctors
practice pattern recognition, not diagnosis. They've
seen that problem before, so they know how to solve
it. The problem with the pattern recognition approach
is that you can only solve problems that you've solved
before

[CpnCrunch]

So basically you're saying that pilots should be able to diagnose problems better than their AMEs because AMEs are mostly lazy, incompetent crooks?

[Colonel Sanders]

That's a tad harsh, but what I have observed over
the last 5 decades is that if you want something
done right, you'd better do it yourself.

This is true of the fields of carpentry, plumbing,
painting, electrics, electronics, software, aviation,
medicine and law, to name a few.

You might have heard of Mike Holmes on TV. He
has made a career of cleaning up after other
contractors, whom he famously describes as
"90% crooks and incompetents".

So, go crap on Mike Holmes, ok? He clearly
doesn't know as much about the trades as
you do.

[rigpiggy]

Most are hard working, knowledgeable etc...... however I know a few that I wouldn't trust. Had one change out the generator, signed it out serviceable, 1200$. Took it flying, same issue, discussed it with my stepfather, they hadn't motored the genny, flashed the field. fixed it ourselves!

[Colonel Sanders]

When I was a kid, a very long time ago, I spent a lot of
time on my grandfather's farm in Kakabeka Falls.

If your motorcycle broke, you fixed it. If the tractor broke,
you fixed it. If the mower broke, you fixed it. If the
raker broke, you fixed it. If the bailer broke, you fixed it.
I cannot imagine bailing hay without a toolbox of shear
bolts and a couple wrenches.

The list goes on, and on. If you wanted a building, you
built it. If the door didn't work, you fixed it. If the water
pump didn't work, you fixed it. If your car didn't work,
you fixed it.

Can anyone spot a pattern? I think I wired my first 3-way
switch in a barn when I was eight years old, which I would
argue is more complicated than the 12 VDC charging system
in a light single.

A different generation, I suppose. We weren't all
Starbucks babies with manicures that called in the
trades when we had a flat tire or a dead battery

[KISS_MY_TCAS]

The older we get, the better we were.

Although unfortunately, I do agree with Col Sanders for the most part.

[CID]

A little knowledge is a dangerous thing sometimes. I've witnessed some know-it-alls really screw things up on an airplane because they figured they knew better. I've also seen a pilot cycle the circuit breaker on a system that locked itself out to prevent reset after failure.

And somewhat related to this story, I know about a guy who charged his batter in his airplane before he flew it because he was convinced that was how it got charged.

Trying to shame people into taking matters in to their own hands because these systems are "simple" is just dangerous. The right thing to do is either go and get formal training to troubleshoot these systems or get a good AME.

Isn't that the simplest thing?

Mike Holmes is in an industry that is barely regulated. It's apples and oranges. The buyer must beware no matter what the industry but aviation is not the same as home construction in this regard.

In fact, If I had a mechanic that kept telling me a system was fixed but it wasn't, I would be making a call to TC. This may not be the first time he's screwed up and maybe he doesn't deserve a license.

Sorry, but you go ahead and feel superior for understanding a few technical things that other pilots don't but you're not doing anybody any favours with this really poor advice.

[Colonel Sanders]

you're not doing anybody any favours with this really poor advice

Maybe some day I will be able to fly and fix an airplane as well as you

A little knowledge is a dangerous thing

You clearly know more about that than I, so I will additionally defer to
your expertise on that as well.

[The Weasel]

That's a tad harsh, but what I have observed over
the last 5 decades is that if you want something
done right, you'd better do it yourself.

This is true of the fields of carpentry, plumbing,
painting, electrics, electronics, software, aviation,
medicine and law, to name a few.

You might have heard of Mike Holmes on TV. He
has made a career of cleaning up after other
contractors, whom he famously describes as
"90% crooks and incompetents".

So, go crap on Mike Holmes, ok? He clearly
doesn't know as much about the trades as
you do.

In a way, I do agree with Col Sanders. There's far too many AMEs nowadays who have become 'change-enieers' with little real troubleshooting going on. Then again, one could also say that there's plenty of pilots who don't really know what they're doing. Far too many have problems with basic journey log entries...