Stranded - need alternator help

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AA5Bman

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He who ironically no longer flies an AA5B
Hey everyone I am stranded at the moment. Took off, got an alternator inop light and faint smell of burning rubber. Landed, took off the cowl, and somehow I am obviously missing the bolt that holds the alternator in place.

I don’t have many resources at the moment being away from home on a holiday weekend. Can anyone help me figure out the right part number for this missing bolt? I am hopeful that I might be able to overnight the bolt here and have a local mechanic install it on Monday.

IO-470S with Plane Power alternator

upload_2021-11-27_9-47-46.jpeg
 
Take a ride to an Ace Hardaware with measurements, get a long bolt & nut, and a bunch of washers, maybe a hack saw if the bolt needs to be custom length. 2 wrenches. That’s all I got.

Fix it right when you get home.

Also, if you let us know where you are, maybe someone on POA can help.
 
I wonder if there's any way to get plane power's phone # or website and call them and ask?
 
Thanks everyone. Looks like I couldn’t get my hands on a bolt even if I could figure out which one it is (due to the holiday weekend) and the hardware store route is not going to fly with the shmancy FBO here, although it wouldn’t bother me as a short term fix. Gonna borrow a car and deal with it later. :(
 
That burning rubber smell was likely the drive belt.

If it’s toast it would require prop removal to replace.

There are folks that keep a belt ty-wrapped to the case for that reason.

Of course ; then you never need it.
 
Hardware store stuff will get you home, but I suspect the missing hardware was not properly installed to begin with.
 
AA5Bman said:
Thanks everyone. Looks like I couldn’t get my hands on a bolt even if I could figure out which one it is (due to the holiday weekend) and the hardware store route is not going to fly with the shmancy FBO here, although it wouldn’t bother me as a short term fix. Gonna borrow a car and deal with it later. :(
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What does the FBO have to do with it?
 
Magman said:
That burning rubber smell was likely the drive belt.

If it’s toast it would require prop removal to replace.

There are folks that keep a belt ty-wrapped to the case for that reason.

Of course ; then you never need it.
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That installation is on a bigger Continental. No prop removal necessary.
 
SkyDog58 said:
POA never disappoints when it comes to having folks advising others to break regulations and/or to perform unairworthy maintenance. Or frequently both.
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It's an alternator bolt. Not an engine bolt or wing bolt. An AN bolt has a tensile strength of around 125,000 PSI; a Grade 5 industrial bolt has a tensile of 120,000 PSI. A Grade 8 bolt is 150,000 PSI. The AN bolt is made of better stuff that is much more crack-resistant. More ductile. Bends or stretches more before it fails. Has a better plating.

Yeah, might be against the regs.

43.13 Performance rules (general).
(b) Each person maintaining or altering, or performing preventive maintenance, shall do that work in such a manner and use materials of such a quality, that the condition of the aircraft, airframe, aircraft engine, propeller, or appliance worked on will be at least equal to its original or properly altered condition (with regard to aerodynamic function, structural strength, resistance to vibration and deterioration, and other qualities affecting airworthiness).

I have seen much more dangerous modifications on airplanes. Much worse. I wouldn't tell someone to do it, but in Canada, if I was in a bad spot, and it was my airplane, I just might, and reference this in the maintenance release: https://tc.canada.ca/en/corporate-s...criteria-classification-modifications-repairs
 
SkyDog58 said:
POA never disappoints when it comes to having folks advising others to break regulations and/or to perform unairworthy maintenance. Or frequently both.
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Yah, I would want it done correctly and functionally checked out before going anywhere..
 
Dan Thomas said:
That installation is on a bigger Continental. No prop removal necessary.
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Are alternator belts an aircraft specific part - i.e. do you have to order a TCM or Lycoming part number belt, or just one that is the same size, shape, and type? Or can they be replaced with a link-belt style. That would not require prop removal in any situation, or could be used as a temporary fix. Just a question for others to ponder as I only fly a small continental without a belt at all.
 
rotormatic1 said:
Yes. On TC aircraft.
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I guess I was wondering how often this was used in the real world.



  • AC 23-27- PARTS AND MATERIALS SUBSTITUTION FOR VINTAGE AIRCRAFT
    APPENDIX 1
    PART SUBSTITUTIONS
    1. DRIVE BELTS
    a. Alternator or Generator Belts.
    (1) For aircraft where the manufacturer no longer sells the original alternator or
    generator belt, you may use a belt made by the same belt manufacturer if the original part
    number is known. If the original part number is not known or the belt is no longer available, you
    may use a belt manufactured to a known specification such as SAE J636 and the belt properly
    fits the application. Pay special attention to fit of the belt to the pulley and proper tension of the
    belt. We highly recommend the use of technical information from similar aircraft.
    (2) The SAE J636 specification covers standard dimensions, tolerances, and methods of
    measurement of V-belts and pulleys for automotive V-belt drives. The V-belts that Piper
    supplies for the PA28-140 conform to this specification.
    Approval: This is a minor alteration and you may document it by a logbook entry. The logbook
    entry must reference the original (if available) and replacement belts' specification and
    manufacturer's identification.
 
Matthew Rogers said:
I guess I was wondering how often this was used in the real world.
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Matthew Rogers said:
AC 23-27- PARTS AND MATERIALS SUBSTITUTION FOR VINTAGE AIRCRAFT
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It depends on the aircraft model. The AC is more restrictive than say the "owner-produced" rules which allow cost or other issues to be considered. But for some models that AC is used on a regular basis. However, if the OEM still readily offers the belt for sale the AC usually can't be used as a reference.
 
SkyDog58 said:
POA never disappoints when it comes to having folks advising others to break regulations and/or to perform unairworthy maintenance. Or frequently both.
Click to expand...


SkyDog58 said:
POA never disappoints when it comes to having folks advising others to break regulations and/or to perform unairworthy maintenance. Or frequently both.
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If he were to locate to correct AN hardware, “Replacement or adjustment of nonstructural standard fasteners incidental to operations” is allowed.
 
In some applications, that's a drilled/safetied bolt. But in this situation, I'd go outlaw and put a hardware store bolt and locknut on it and take it home. Or I'd cut the belt off and fly home VFR with everything possible turned off from an electrical perspective.
 
Clip4 said:
If he were to locate to correct AN hardware, “Replacement or adjustment of nonstructural standard fasteners incidental to operations” is allowed.
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An alternator mount bolt which causes the alternator to not function correctly while slipping the belt to the point where the pilot can smell burning rubber is “incidental to operations?”

When I read the section you quoted I think of things like screws that hold light covers or interior panels on. Not engine accessory bolts.
 
The bolt is a standard fastener and isn’t structural. Structural fasteners would be used to attach wings, landing gear, or engines.

Even changing a tire or battery involves removing and reinstalling bolts and nuts.
 
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kyleb said:
In some applications, that's a drilled/safetied bolt. But in this situation, I'd go outlaw and put a hardware store bolt and locknut on it and take it home. Or I'd cut the belt off and fly home VFR with everything possible turned off from an electrical perspective.
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Yeah, odds are I’d do the same if I was in a bind. Amusing thing is, that same AN bolt off the shelf at Ace is likely cheaper by a factor of x10 than whatever spruce or the OEM sells it for. Stupid PMA! :)
 
Automotive store would have a bolt to fit. This is where I suppose a good relationship with your A&P is a good thing, talk it over, get the bolt, send him a pic, get a sign off, fly home. I suppose you would need few skills though, tools could be bought the automotive store too.
 
I'm just wondering what everyone thinks would happen if, hypothetically, he found a functionally correct but not FAA approved bolt, tightened it up and flew home. I mean are people here worried that this would present a safety-of-flight issue, or just a paperwork issue? If an A&P came over and said, "Yep, that there bolt's missing, lemme screw in a new one," would he be expected to make a log entry for replacing a missing bolt?
 
It looks like it is the long bolt that goes the whole length of the alternator. I am surprised you were able to fly far if it weren't there in the first place. Or did it fall off during flight?
 
OP checking back in, now home after a long drive. Thanks for the thoughts and comments.

So... with a bunch of time to think about it, my thoughts are as follows:

1) If I were coming out of a backcountry strip or if I had been by myself, I think in retrospect the thing to do was to cut the alternator belt off to eliminate further damage, smoke, or fire, and limp home without radios. I say that because this is pretty rural country and it was a perfect VFR day. But with the whole family on board, this wasn’t really that realistic and, frankly, I didn’t think about it until we were already halfway home.

2) I honestly think the hardware store is a perfectly reasonable solution in a pinch, but it’s probably not legal. I said the FBO wouldn’t go for it because I wasn’t going to be able to do that myself. Yes, I could have gone to the hardware store and figured out a workable bolt, but there’s no way to get the bolt in without loosening the tensioning bolt on the other side of the alternator, and that would mean loosening that bolt, inserting the new one, and re-tensioning the alternator. Having never tensioned an alternator belt, I would have been purely guessing, and today was not the day for that.

3) With the above in mind, the only way the hardware store solution would work would be for me to find the bolt and ask the local A&P to install it, and without the correct hardware and after talking to them about possible solutions it was clear there was no way they were going to do that for me. And, again, it’s probably not legal, so I’m not surprised they wouldn’t do it for a stranger, especially on a Saturday the weekend after Thanksgiving.

Anyway, I asked the local FBO to figure out the part and get it back together and I’ll figure out a way to return the car and pick up the plane. Pain in the ass, but so it goes.

You know what was the worst part? The worst part is that this actually happened on what was supposed to be a quick sight-seeing flight with my 70 year old mom, who is terrified of and convinced our plane is a death trap. The plan was to take her on a beautiful sightseeing flight around the mountains for an hour or so and then the family would come meet us at the airport and we’d load up the kids and fly home. We’ve flown that plane 400+ hours without hardly a fart and certainly never been stranded, and on the day I go to take up my nervous nelly mom we end up with an “emergency” landing. Sheesh. Life.
 
Rgbeard said:
I’m amused that this thread has everything except his location and any information about the aircraft.
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It is more amusing that people have their panties in a bunch over using the "wrong" bolt when the "approved" bolt is the one that failed.

And, the AN spec has been ****ing obsolete since 1950...
 
Capt. Geoffrey Thorpe said:
It is more amusing that people have their panties in a bunch over using the "wrong" bolt when the "approved" bolt is the one that failed.

And, the AN spec has been ****ing obsolete since 1950...
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Devil's advocate: there's no evidence the "approved" bolt actually failed. Installation of said bolt was likely done inappropriately.
 
RyanB said:
Yeah, odds are I’d do the same if I was in a bind. Amusing thing is, that same AN bolt off the shelf at Ace is likely cheaper by a factor of x10 than whatever spruce or the OEM sells it for. Stupid PMA! :)
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PMA? I was unaware that a PMA was required for standard parts such as hardware. Has that changed recently?

Also does Ace hardware carry AN hardware? If a hardware store does actually sell AN, MS, or NAS hardware and has documentation that proves it was produced to that standard, would it be ok to install on a type certificated aircraft?
 
PaulS said:
Automotive store would have a bolt to fit. This is where I suppose a good relationship with your A&P is a good thing, talk it over, get the bolt, send him a pic, get a sign off, fly home. I suppose you would need few skills though, tools could be bought the automotive store too.
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I doubt if many mechanics would do a sign off for a pilot performed installation of an unapproved part. I know I wouldn’t.
 
eman1200 said:
I wonder if there's any way to get plane power's phone # or website and call them and ask?
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I’m really surprised in this era of iPads and other tablets being carried by the vast majority of pilots that more of those pilots don’t have pdf versions of all of their manuals (parts and maintenance) and STC ICAs on those tablets. It is something that I would do as an owner.
 
Lindberg said:
I mean are people here worried that this would present a safety-of-flight issue, or just a paperwork issue?
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Or what if the OP would have procured the proper AN hardware and install instructions, installed the hardware per those instructions to include the proper torque, performed a ground run function check to check for serviceability, and completed the log entry referencing the install instructions and Part 43 Appendix A(c)(26) as mentioned above?

He could even in throw in an ops check flight with sign off per 91.407. While the Coleal LOI does not offer the free-for-all of preventative maintenance tasks as some people believe, it does provide an expanded definition of what those existing 32 “categories” can include. And this scenario is a good one to use.
 
SkyDog58 said:
PMA? I was unaware that a PMA was required for standard parts such as hardware. Has that changed recently?

Also does Ace hardware carry AN hardware? If a hardware store does actually sell AN, MS, or NAS hardware and has documentation that proves it was produced to that standard, would it be ok to install on a type certificated aircraft?
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Just using it as an example. How many times have we seen non-PMA’d parts matched up against their PMA equivalent and compared the prices of the two? That little stamp of approval hikes the price by tenfold.

Who knows if Ace sells AN hardware, they probably don’t, that was just the example used in an above message. Odds are, NAPA or Advanced would carry something like it though.
 
1. That belt doesn't need to be cut to remove it. Push the alternator inboard a bit and work it off the pulley. It's a Continental, not a Lyc.

2. Do not use hardware-store belts. They are usually FHP (fractional horsepower) belts, intended for furnace fans and table saws and stuff like that. They will not transmit the one or two or three HP required to drive an alternator at full load for very long. FHP belts are nowhere near as strong as automotive V-belts, and the V-angles are also different. Then there are industrial belts, another animal again. Like the law says, use it if the belt manufacturer's part number is listed in the airplane's parts catalog.

And don't use link-belts. They are FHP or industrial belts.

3. The bolt likely fell out because its nut was never tightened. Maybe never had a nut. They typically use a self-locking nut in that spot, and they don't fall off if they're run far enough onto the threads. Only once have I ever seen the head of a bolt pop off, and that was on an old airplane. Bolt was rusty. Someone had likely overtorqued it at least once. And it was an AN bolt.

I once ferried a 172 to our shop. We opened everything up and found that the wing strut bolts at the fuselage connection had no nuts on them and weren't even all the way in. A friend opened up a nearly-new 172 and found the nuts missing off the strut-to-wing bolts. Never had them, and the torque seal paint was on the threads. Some hungover inspector at the factory, probably. It happens.
 
Der Fliegermeister said:
Devil's advocate: there's no evidence the "approved" bolt actually failed. Installation of said bolt was likely done inappropriately.
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The point is that the authorized bolt by an authorized mechanic failed badly. It does not mean an unauthorized bolt should be used by an unauthorized mechanic. But some judgement can be exercised until a proper solution can be found. One can fly legally without an alternator, or even without a battery depending on airspace. The fact that this pilot looked under the cowling and found a missing bolt does not change what he was allowed to do if he never looked in the first place. The safest option was to drive home, which is what he did, but I don't think there is a clear answer here.
 
sarangan said:
One can fly legally without an alternator, or even without a battery depending on airspace.
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FYI: short of using a SFP, the legal side depends on the aircraft configuration and not the airspace use.
 
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