1969 Piper Cherokee alternator?

It is not illegal to fly a PA28-140; VFR in DAYLIGHT in good weather with the alternator turned off and most of the electrical equipment shut down. Read the MEL for more information. Furthermore, the cost of leaving the airplane and getting a ride home, then getting a ride back to pick up the airplane after you wait for the parts is likely much higher than the freight to return the alternator if that is not the problem. Compare that to your mechanic traveling out to you to TS and then again for the repair. You come out a lot cheaper if your mechanic has parts on hand before you go there. You and I obviously don't see eye to eye on this at all. Sorry I chimed in. My bird would be scheduled into the shop by now. It would be done.
 
It is not illegal to fly a PA28-140; VFR in DAYLIGHT in good weather with the alternator turned off and most of the electrical equipment shut down.

There's a difference between turning off an alternator and knowingly operating the aircraft with a defective non operating one.

Read the MEL for more information.

You have an approved MEL for your airplane? Most GA single owners don't bother to go through the process of getting an MEL approved for part 91 operations.

And I can assure you, the MMEL for single engine doesn't list the alternator as an approved deferable item. https://fsims.faa.gov/wdocs/mmel/se rev 1.htm

Furthermore, the cost of leaving the airplane and getting a ride home, then getting a ride back to pick up the airplane after you wait for the parts is likely much higher than the freight to return the alternator if that is not the problem. Compare that to your mechanic traveling out to you to TS and then again for the repair. You come out a lot cheaper if your mechanic has parts on hand before you go there. You and I obviously don't see eye to eye on this at all. Sorry I chimed in. My bird would be scheduled into the shop by now. It would be done.

So it's all about the cost, again? Take a chance to save a few bucks?
 
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Few bucks? Folks do fly LOP for that reason.

All of GA is a shadow of what it was years ago because of “ a few bucks”!

Even Presidential Aircraft used Economy Cruise at times!
 
You and I obviously don't see eye to eye on this at all.
Obviously. Especially when you push cost savings at the expense of following the rules. And then encourage another individual to follow that same path. My 1st post on PoA was due to the same situation except the info being stated would have cost an individual $1000s vs the $100s in your posts.
It is not illegal to fly a PA28-140; VFR in DAYLIGHT in good weather with the alternator turned off and most of the electrical equipment shut down. Read the MEL for more information.
And here it continues. I don’t know who told you this but that is incorrect. As stated above turning off an inoperative system doesn’t get you past GO from an airworthy side. Same with your MEL comment. I’m sure the numbers of PA28-140s with a valid FSDO authorized MEL are quite few, if any. And even if you had an MEL that permitted the deferral of a single alternator, it could not be used by the OP. So I don't follow your point in bringing up the MEL at all.
 
No.

1. Alternator is not working, so no power source other than battery.
2. Breaker is tripping because alternator is shorted and battery is backfeeding the short.
It could be a simple thing like the alternator output cable chafing on the engine mount and shorting. That does the engine mount no good at all. There are plenty of places for a short in that line besides within the alternator: The cable terminal at the alternator, the cable anywhere between the alternator and the breaker, including at or inside any noise filters on the firewall, and so on. Shorted diodes are rare indeed. Two or more shot at the same time is so rare it's not funny. If they are, it could be because there was a short in the output line to ground, causing massive alternator overload, cooking the diodes. The breaker would have popped, isolating the battery from the alternator and the shorted cable, but the alternator output would still have been grounded through that short. Unless that short is found and fixed, the new alternator will just get cooked, too.
 
It is not illegal to fly a PA28-140; VFR in DAYLIGHT in good weather with the alternator turned off and most of the electrical equipment shut down.

If the electrical system is not serviceable at departure, then it is in fact illegal. A PA28 is designed and built with a functioning electrical system. It is part of its type design. If it doesn't meet the type design, it can't be legally airworthy. A J3, not so much.

If you choose to shut it down, that is a different story. You can also choose to turn it on again!
 
Did you know that most people in Europe believe everything is illegal unless a law from the government make it legal? Most people in the US believe everything is legal unless a law specifically makes it illegal. In the US most people believe common sense has value, that life and freedom cannot exist without risk and responsibility. Everything in aviation is a compromise because there is no such thing as perfection. Cost vs Risk vs Benefit. That is the way of things. Do you want to live like the Europeans? Always afraid of breaking the rules to the point of inaction and enslavement? I don't. I won't. I will evaluate my situation and make the best choices I can considering safety and risk vs reward. Everything in aviation cost money. Everything in aviation involves risk. Everything in aviation requires aviation decisions both on the ground and in the air.

Which country do you want to live in?
 
... Most people in the US believe everything is legal unless a law specifically makes it illegal. In the US most people believe common sense has value, that life and freedom cannot exist without risk and responsibility...

um
 
Did you know that most people in Europe believe everything is illegal unless a law from the government make it legal? Most people in the US believe everything is legal unless a law specifically makes it illegal. In the US most people believe common sense has value, that life and freedom cannot exist without risk and responsibility. Everything in aviation is a compromise because there is no such thing as perfection. Cost vs Risk vs Benefit. That is the way of things. Do you want to live like the Europeans? Always afraid of breaking the rules to the point of inaction and enslavement? I don't. I won't. I will evaluate my situation and make the best choices I can considering safety and risk vs reward. Everything in aviation cost money. Everything in aviation involves risk. Everything in aviation requires aviation decisions both on the ground and in the air.

Which country do you want to live in?


I thought we were discussing a broke alternator. o_O
 
I don't. I won't.
Ha. If you want to be an outlaw and live on the edge, fine. Just don’t bring any unsuspecting people down that slippery slope with you like in this thread. I’ve seen too many people get the short end of the stick from advice by people like yourself and at a cost much greater than the “savings” you propose.
life and freedom cannot exist
It has zero to do “life and freedom” and everything to do with you being too cheap to follow a few basic rules like fly an airworthy aircraft. No different than people who want $200/20 minute annuals because they want that extra cash to spend on their "life and freedoms." If your aviation "freedom" is that important there's a simple solution called E/AB. :rolleyes:
 
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My question about troubleshooting was NOT a question about the advisability of flying the plane to the A&P. I am not opining on that issue.

How about this?
1. Physically disconnect the alternator, both field and output cables from the alternator. Insulate both field and output cable ends
2. Reset the breaker.
3. Start the plane with the ALT master switch ON.
4. Does the breaker pop?

I *think* that will tell you if the short is somewhere other than inside the alternator.
 
Dom
That looks a good way to diagnose but it’s a little more complicated.

Every 140 I recall you have to pull the prop and nose bowl and temporarily

reinstall prop just to adjust belt tension.

I don’t recall if you can gain access to cables w/o doing the same.

We are in the middle of a field.
 
Did you know that most people in Europe believe everything is illegal unless a law from the government make it legal? Most people in the US believe everything is legal unless a law specifically makes it illegal. In the US most people believe common sense has value, that life and freedom cannot exist without risk and responsibility. Everything in aviation is a compromise because there is no such thing as perfection. Cost vs Risk vs Benefit. That is the way of things. Do you want to live like the Europeans? Always afraid of breaking the rules to the point of inaction and enslavement? I don't. I won't. I will evaluate my situation and make the best choices I can considering safety and risk vs reward. Everything in aviation cost money. Everything in aviation involves risk. Everything in aviation requires aviation decisions both on the ground and in the air.

Which country do you want to live in?
Like I said already, that alternator output cable might be shorting against the engine mount, which does the mount no good at all. Arcing there burns away metal from that thinwalled tubing, weakening it so that it can crack and break. In flight. Like that's something that we can ignore and just go fly it? What average owner has the ability to determine the safety of such damage?

There is so much that the average owner simply does not know. Stuff that can kill him. Shoot, maybe someone tied that cable to the fuel line from the strainer to the carb, and it's been chafing and shorting against the steel braid in that hose. What then?? Fire. Maybe that cable has come off the terminal on the alternator and is waving around and contacting a lot of stuff and maybe could foul the throttle or mixture controls. That would easily explain a dead alternator and popped breaker. Could be lots of damage, like burned throttle and mixture connections that are now ready to fail. Ugh.

Sure, you're free to do whatever. At your own risk. Advising someone else to do the same without any thorough inspection is dangerous.
 
Dom
That looks a good way to diagnose but it’s a little more complicated.

Every 140 I recall you have to pull the prop and nose bowl and temporarily

reinstall prop just to adjust belt tension.

I don’t recall if you can gain access to cables w/o doing the same.

We are in the middle of a field.

It can be done fairly easily without removing the cowling. Just open the top right engine cowl as you would to check the oil level.
 
Like I said already, that alternator output cable might be shorting against the engine mount, which does the mount no good at all. Arcing there burns away metal from that thinwalled tubing, weakening it so that it can crack and break. In flight. Like that's something that we can ignore and just go fly it? What average owner has the ability to determine the safety of such damage?

There is so much that the average owner simply does not know. Stuff that can kill him. Shoot, maybe someone tied that cable to the fuel line from the strainer to the carb, and it's been chafing and shorting against the steel braid in that hose. What then?? Fire. Maybe that cable has come off the terminal on the alternator and is waving around and contacting a lot of stuff and maybe could foul the throttle or mixture controls. That would easily explain a dead alternator and popped breaker. Could be lots of damage, like burned throttle and mixture connections that are now ready to fail. Ugh.

Sure, you're free to do whatever. At your own risk. Advising someone else to do the same without any thorough inspection is dangerous.

Yep. Well said! :)
 
:) I think this is the most complicated alternator discussion I've ever seen.

Many alternators, or maybe more accurately the voltage regulator, won't work without a load...may even damage the alternator. A shorted cell in a battery can take out some alternators, under some circumstances. Or in other words, many alternators don't like an open circuit, and none of them like a short.

So how about check the battery.
 
So what of the “Reluctant A & P”?

These people are not Public Servants so they can accept or reject any work

that comes their way.

I tried to put myself in the Tech’s position.

Getting Aircraft A & B finished as soon as parts arrive is a priority.

The end of the month will soon be here so there will be others out of Annual.

Already committed to Aircraft C and D for beginning of next month.

Wife reminds me of wedding and grand kids sports events.

From multiple sources here the consensus is there may well be more issues

involved.

Attaching Mount or bolts worn? Cables or terminations need replacement?

Prop Bolts “ pulled” if previously over torqued? Totally unrelated problem?

I know from previous “ Road Trips” that there is often a part or tool that gets left

at home.

So it’s possible there could be multiple trips .

Considering commitments already made and ordering parts it could even drag

into snow season.

Would the aircraft be able to fly out then?

My belief is once you start on a project then you “own” it.

So if if this person is considered a client rather than a really , really good

friend I would decline the project and suggest the owner contact someone else.

The problem is that everyone else is even further away.
 
So what of the “Reluctant A & P”?

These people are not Public Servants so they can accept or reject any work

that comes their way.

I tried to put myself in the Tech’s position.

Getting Aircraft A & B finished as soon as parts arrive is a priority.

The end of the month will soon be here so there will be others out of Annual.

Already committed to Aircraft C and D for beginning of next month.

Wife reminds me of wedding and grand kids sports events.

From multiple sources here the consensus is there may well be more issues

involved.

Attaching Mount or bolts worn? Cables or terminations need replacement?

Prop Bolts “ pulled” if previously over torqued? Totally unrelated problem?

I know from previous “ Road Trips” that there is often a part or tool that gets left

at home.

So it’s possible there could be multiple trips .

Considering commitments already made and ordering parts it could even drag

into snow season.

Would the aircraft be able to fly out then?

My belief is once you start on a project then you “own” it.

So if if this person is considered a client rather than a really , really good

friend I would decline the project and suggest the owner contact someone else.

The problem is that everyone else is even further away.
It's all part of airplane ownership in a shrinking industry. Not likely to get any better, either, as long as mechanics are often underpaid compared to auto or HD mechanics, and as long as many folks can barely afford to own an airplane. As a DOM in a flight school I sometimes had to contract mechanics to drive considerable distances to repair an airplane that had an undeferrable snag at some out-of-the-way airport, a long way from home. There were times I had to do it myself, when they were closer. Flaps that wouldn't retract, strange smoky smells in the cockpit, CO monitor indicating carbon monoxide, failed regulator, failed carb heat control. One makes a best guess and takes a bunch of stuff along. And sometimes it's not enough. Still, it doesn't justify taking chances.
 
So what of the “Reluctant A & P”?

These people are not Public Servants so they can accept or reject any work

that comes their way.

I tried to put myself in the Tech’s position.

Getting Aircraft A & B finished as soon as parts arrive is a priority.

The end of the month will soon be here so there will be others out of Annual.

Already committed to Aircraft C and D for beginning of next month.

Wife reminds me of wedding and grand kids sports events.

From multiple sources here the consensus is there may well be more issues

involved.

Attaching Mount or bolts worn? Cables or terminations need replacement?

Prop Bolts “ pulled” if previously over torqued? Totally unrelated problem?

I know from previous “ Road Trips” that there is often a part or tool that gets left

at home.

So it’s possible there could be multiple trips .

Considering commitments already made and ordering parts it could even drag

into snow season.

Would the aircraft be able to fly out then?

My belief is once you start on a project then you “own” it.

So if if this person is considered a client rather than a really , really good

friend I would decline the project and suggest the owner contact someone else.

The problem is that everyone else is even further away.
So what's your point? It's okay to fly an unairworthy aircraft to a mechanic because he's busy?
 
My point it’s not my concern .

I’ll leave the decision to the owner.
 
If I was wearing the hat of the “Reluctant A & P” and declined to get involved

then I am totally out of the picture.

Maybe the next post may be more confusing?
 
Alternator failures happen all the time, but popping breakers at the same time is much rarer. Anyway, the point is this: Alternator brushes wear out and the alternator quits. That's why Cessna and other OEMS have, in their inspection programs, a 500-hour alternator internal inspection. Same goes for magnetos. For most airplanes this never gets done; these things are run to failure. And if one of them fails at some remote spot, you're going to spend a lot more money getting it fixed than if you'd just done stuff right and on time. Sometimes you can add in hotels and meals and missed days at work if you want a real picture of what deferred maintenance can add up to.
 
I don't get it. What is the big deal about getting a ferry permit? Probably a mechanic needs to look at it to ensure it is safe for flight. I have done them over the phone. It depends on the particular relationship (does the mechanic know the aircraft and trust the owner).

So he/she looks to ensure it is safe. Cut the belt if warranted. Disconnect wires if needed. Can also get a start on troubleshooting. Some paperwork. Not really a big deal.
 
I don't get it. What is the big deal about getting a ferry permit? Probably a mechanic needs to look at it to ensure it is safe for flight. I have done them over the phone. It depends on the particular relationship (does the mechanic know the aircraft and trust the owner).

So he/she looks to ensure it is safe. Cut the belt if warranted. Disconnect wires if needed. Can also get a start on troubleshooting. Some paperwork. Not really a big deal.
So someone who knows what they're looking at needs to look it over. Nobody wants to come, at least for free. Would I, as a mechanic, trust the average owner to check it over? Nope. Way too much liability.
 
So someone who knows what they're looking at needs to look it over. Nobody wants to come, at least for free. Would I, as a mechanic, trust the average owner to check it over? Nope. Way too much liability.

As I wrote, depends on the relationship. I have done it once or twice using pictures from pilots I trust.
 
At this point, probably your best option is just to bury the whole aircraft in the sand. Make sure to drain the fuel and oil first, so as not to make a hazard. Then come back for it later after things have calmed down.
 
My belief is mags and alternators often fail in flight but are not discovered

until the next preflight inspection.

If the breaker popping was noticed in the descent; which option should

the pilot follow?

Follow FAR 91-7 b and recognize their responsibility to discontinue flight after

an electrical failure and land at the strip with no services ?

OR

Follow FAR 91-7 b and exercise their authority to determine if the aircraft is safe

for flight and continue on to the airport where repairs can be readily

accomplished?


While you fire away I’ll go download my NASA Form!
 
Maybe the next post may be more confusing?

My belief is mags and alternators often fail in flight but are not discovered

until the next preflight inspection.

If the breaker popping was noticed in the descent; which option should

the pilot follow?

Follow FAR 91-7 b and recognize their responsibility to discontinue flight after

an electrical failure and land at the strip with no services ?

OR

Follow FAR 91-7 b and exercise their authority to determine if the aircraft is safe

for flight and continue on to the airport where repairs can be readily

accomplished?


While you fire away I’ll go download my NASA Form!
Well I guess you did warn us.o_O
 
Alright back to my original post. I heeded the advice and had an AP look at the aircraft. Found an issue with the alternator cable, repaired and runs fine now. I seem to be losing oil from a still, unknown location. He tightened up some loose ends so that may help. He pulled the plugs and the bottom on the #3 cylinder was coated in oil. Did a compression check and all cylinders above 70. He stated may have an issue with the rings but the compressions are good so it needs to flown and monitor the situation. The engine is running great no issues. He told me be prepared to possibly replace the #3 cylinder as he bores coped it and it’s blackened inside. Any thoughts or recommendations?
 
He pulled the plugs and the bottom on the #3 cylinder was coated in oil.
He told me be prepared to possibly replace the #3 cylinder as he bores coped it and it’s blackened inside.
Don't quite follow the "blackened" comment but how is you oil consumption? Sometimes when an oil control ring fails you'll get more oil residue in that cylinder. Maybe he saw something else as well? Not much else to do at this point if engine running good and just wait till the annual.
I heeded the advice and had an AP look at the aircraft. Found an issue with the alternator cable, repaired and runs fine now.
Glad you didn't buy a new alternator to have on hand. ;)
 
Don't quite follow the "blackened" comment but how is you oil consumption? Sometimes when an oil control ring fails you'll get more oil residue in that cylinder. Maybe he saw something else as well? Not much else to do at this point if engine running good and just wait till the annual.

Glad you didn't buy a new alternator to have on hand. ;)
Not sure myself. Said the cylinder looked “blackened” with a bore scope. Oddly enough my oil consumption is high but it started suddenly. He said it’s running fine and the engine is good. Wait it out until something is noticed and just keep adding oil as needed.
 
Alright back to my original post. I heeded the advice and had an AP look at the aircraft. Found an issue with the alternator cable, repaired and runs fine now.
What was the issue? Be nice to know that. Fell off? Loose and rotating cable terminal shorting on something? Why did the breaker pop if there was no short?
 
What was the issue? Be nice to know that. Fell off? Loose and rotating cable terminal shorting on something? Why did the breaker pop if there was no short?
As far as the alternator, the wire is an old braided, fiber wire which had some chafing. All good now.
 
Glad it all turned out well for you.
 
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