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Jay Honeck
June 20th 07, 04:54 PM
When we flew our '75 Warrior, it developed a problem with the
alternator going off-line in flight. This was preceeded by the
ammeter needle bouncing crazily and finally pegging at 60 amps.

I fixed that problem by spending an hour tracing all the electrical
lines, and tightening connections. The main culprit was a wire
connector that was screwed into the backside of the alternator with a
simple phillips screw -- no safety wire, no loc-tite, no nuthin'.
Looked like a ground wire to me, but I'm no mechanic.

I turned it a good two and half turns, and the problem went away,
never to return. We sold the plane in '02.

Recently, Atlas developed a nasty, annoying whine in the headphones.
This developed immediately after I had removed the PS Engineering CD/
Intercom for some panel maintenance, so I naturally assumed that they
were related.

No amount of re-seating, cleaning, wiggling had any effect. My
frustration was mounting.

Then, this past Sunday, I decided to chang the oil after our return
flight from the Cherokee Pilots Association fly-in. It was Fathers
Day, it was 100 degrees in the hangar, and we were both melting, but I
decided to de-cowl the plane in order to make the oil change easier,
and to trace the wiring -- just in case it was another loose
connection somewhere.

Of course, the first place I looked was the backside of the
alternator, and, lo and behold, the same damned wire was loose! A
few turns to tighten, and voila! -- no more whine. (I traced the rest
of the wiring, while I was at it, and found a couple of broken zip
ties, and one broken wire -- a lead going to one of my cylinder
heaters. It's broken right where it goes into the cylinder -- THAT
looks like absolutely no fun to repair...)

Anyway, what should I put on this stupid screw to stop it from
vibrating loose? LocTite? Another lock washer? There's no way to
safety wire it...

Thanks!
--
Jay Honeck
Iowa City, IA
Pathfinder N56993
www.AlexisParkInn.com
"Your Aviation Destination

Matt Barrow[_4_]
June 20th 07, 05:57 PM
"Jay Honeck" > wrote in message
oups.com...
> When we flew our '75 Warrior, it developed a problem with the
> alternator going off-line in flight. This was preceeded by the
> ammeter needle bouncing crazily and finally pegging at 60 amps.
>
> I fixed that problem by spending an hour tracing all the electrical
> lines, and tightening connections. The main culprit was a wire
> connector that was screwed into the backside of the alternator with a
> simple phillips screw -- no safety wire, no loc-tite, no nuthin'.
> Looked like a ground wire to me, but I'm no mechanic.
>
> I turned it a good two and half turns, and the problem went away,
> never to return. We sold the plane in '02.
>
> Recently, Atlas developed a nasty, annoying whine in the headphones.
> This developed immediately after I had removed the PS Engineering CD/
> Intercom for some panel maintenance, so I naturally assumed that they
> were related.
>
> No amount of re-seating, cleaning, wiggling had any effect. My
> frustration was mounting.
>
> Then, this past Sunday, I decided to chang the oil after our return
> flight from the Cherokee Pilots Association fly-in. It was Fathers
> Day, it was 100 degrees in the hangar, and we were both melting, but I
> decided to de-cowl the plane in order to make the oil change easier,
> and to trace the wiring -- just in case it was another loose
> connection somewhere.
>
> Of course, the first place I looked was the backside of the
> alternator, and, lo and behold, the same damned wire was loose! A
> few turns to tighten, and voila! -- no more whine. (I traced the rest
> of the wiring, while I was at it, and found a couple of broken zip
> ties, and one broken wire -- a lead going to one of my cylinder
> heaters. It's broken right where it goes into the cylinder -- THAT
> looks like absolutely no fun to repair...)
>
> Anyway, what should I put on this stupid screw to stop it from
> vibrating loose? LocTite? Another lock washer? There's no way to
> safety wire it...

Arc weld it.

Mark Hansen
June 20th 07, 06:25 PM
On 06/20/07 08:54, Jay Honeck wrote:

[ snip ]

>
> Anyway, what should I put on this stupid screw to stop it from
> vibrating loose? LocTite? Another lock washer? There's no way to
> safety wire it...
>
> Thanks!

Can you get a bolt/screw that will fit the threads and which can
be safety wired? ... or would that not be an "approved" part?

The Visitor
June 20th 07, 06:31 PM
Well if conductivity can be maintained, loctite (not red) should be
okay, used sparingly of course. Dare I say a blob of silicone over the
whole thing? Something harde seems scarey to use, like JB Weld or liquid
solder, epoxy glue and such. New lockwashers are probably in order.

I am going to go check my alternators tomorrow....

John

Jay Honeck wrote:

> When we flew our '75 Warrior, it developed a problem with the
> alternator going off-line in flight. This was preceeded by the
> ammeter needle bouncing crazily and finally pegging at 60 amps.
>
> I fixed that problem by spending an hour tracing all the electrical
> lines, and tightening connections. The main culprit was a wire
> connector that was screwed into the backside of the alternator with a
> simple phillips screw -- no safety wire, no loc-tite, no nuthin'.
> Looked like a ground wire to me, but I'm no mechanic.
>
> I turned it a good two and half turns, and the problem went away,
> never to return. We sold the plane in '02.
>
> Recently, Atlas developed a nasty, annoying whine in the headphones.
> This developed immediately after I had removed the PS Engineering CD/
> Intercom for some panel maintenance, so I naturally assumed that they
> were related.
>
> No amount of re-seating, cleaning, wiggling had any effect. My
> frustration was mounting.
>
> Then, this past Sunday, I decided to chang the oil after our return
> flight from the Cherokee Pilots Association fly-in. It was Fathers
> Day, it was 100 degrees in the hangar, and we were both melting, but I
> decided to de-cowl the plane in order to make the oil change easier,
> and to trace the wiring -- just in case it was another loose
> connection somewhere.
>
> Of course, the first place I looked was the backside of the
> alternator, and, lo and behold, the same damned wire was loose! A
> few turns to tighten, and voila! -- no more whine. (I traced the rest
> of the wiring, while I was at it, and found a couple of broken zip
> ties, and one broken wire -- a lead going to one of my cylinder
> heaters. It's broken right where it goes into the cylinder -- THAT
> looks like absolutely no fun to repair...)
>
> Anyway, what should I put on this stupid screw to stop it from
> vibrating loose? LocTite? Another lock washer? There's no way to
> safety wire it...
>
> Thanks!
> --
> Jay Honeck
> Iowa City, IA
> Pathfinder N56993
> www.AlexisParkInn.com
> "Your Aviation Destination
>

Steve
June 20th 07, 07:21 PM
Jay Honeck wrote:
> Anyway, what should I put on this stupid screw to stop it from
> vibrating loose? LocTite? Another lock washer? There's no way to
> safety wire it...

New phillips screw, new external tooth lockwasher, loctite (medium grade
removable type), add it to the list of inspection items when the cowl is
off the airplane.

There may be a drilled head screw/bolt you could use, but you mentioned
there is no way to safety wire it.....I assume that means nothing on the
back of the alternator to wire it to.

Steve

Jay Masino
June 20th 07, 07:23 PM
Jay Honeck > wrote:
> I fixed that problem by spending an hour tracing all the electrical
> lines, and tightening connections. The main culprit was a wire
> connector that was screwed into the backside of the alternator with a
> simple phillips screw -- no safety wire, no loc-tite, no nuthin'.
> Looked like a ground wire to me, but I'm no mechanic.
<SNIP>
> Anyway, what should I put on this stupid screw to stop it from
> vibrating loose? LocTite? Another lock washer? There's no way to
> safety wire it...

"Generally" there's only 2 wires on the alternator; the field wire from
the regulator, and the output. Ground is usually established through
the case of the alternator and associated bracket. If it was a
relatively thin wire, it was more likely that it was the field. If
that's the case, you defintely DON'T want to safety wire it. A fresh
lock washer, and if you absolutely must, a very small dab of Locktite.

There's always a chance that it was some sort of "extra" ground that
someone added, but if that being loose is causing a whine, it seems
like something else is also wrong (and the extra ground is covering it
up).

--- Jay


--

Jay Masino "Home is where My critters are"
http://www.JayMasino.com
http://www.OceanCityAirport.com
http://www.oc-Adolfos.com

RST Engineering
June 20th 07, 07:38 PM
PLEASE, NO LOCTITE. LOCTITE MEANS THAT YOU NEVER WANT TO REMOVE THE SCREW
AGAIN, which is going to play hell if the alternator itself ever craps out.

If it is a bare wire, then no lockwasher in the world will help. Put a crimp
terminal on the wire and then an INTERNAL TOOTH star or splitring
lockwasher. The order of assembly is alternator, crimp terminal,
lockwasher, screw.

Jim

--
"Dream as if you'll live forever. Live as if you'll die today."
--James Dean




"Jay Honeck" > wrote in message
oups.com...
> When we flew our '75 Warrior, it developed a problem with the
> alternator going off-line in flight. This was preceeded by the
> ammeter needle bouncing crazily and finally pegging at 60 amps.

June 20th 07, 09:03 PM
Jay Honeck > wrote:
> When we flew our '75 Warrior, it developed a problem with the
> alternator going off-line in flight. This was preceeded by the
> ammeter needle bouncing crazily and finally pegging at 60 amps. [...]
> The main culprit was a wire connector that was screwed into the
> backside of the alternator with a simple phillips screw -- no safety
> wire, no loc-tite, no nuthin'. Looked like a ground wire to me, but
> I'm no mechanic.

Disclaimer: This is based on experience with ground vehicles and by
looking at the generator setup on a 182. I don't have an A&P; I don't
even have a TG&Y. Some of this may not be allowable owner maintenance.
Some of this may not be allowable on a certificated aircraft. Your
mileage may vary.

Sounds like the field wire to me. A loose ground wire would probably
tend to make the ammeter read less (discharge), rather then pegging at
max charge.

There are some variations, but in general, a generator or alternator
with external regulator will have three connections:

- Main output wire. This carries all of the current coming out of the
generator or alternator. Usually the fattest (thickest) wire on the
device, and often bolted on to a fairly substantial stud - 0.25"/6.3
mm or more diameter. The stud will be insulated from the metal case
of the machine.

- Field wire. The regulator turns this on and off to control how much
current the main wire puts out. This is a relatively thin wire (on
the order of 14 gauge or 1.5 mm^2) and may be bolted to a stud or
screwed to a metal terminal. The stud or screw will be relatively
small, like #8 or #10 (maybe 3 or 4 mm). The stud or terminal will
be insulated from the metal case of the machine.

- Ground connection. Often done through the mounting bolts, but some
may have a separate ground wire or strap. It will be at least as
thick as the field wire and possibly as thick as the main output wire.
It may also be a woven metal strap instead of a wire. This will be
bolted directly to the metal casing of the machine with no insulation.

Again, there are variations, but this is probably the most common setup
on older aircraft.

> Of course, the first place I looked was the backside of the
> alternator, and, lo and behold, the same damned wire was loose! A
> few turns to tighten, and voila! -- no more whine [in radio audio].

Before you fiddle with this, make sure the master is off. For extra
safety, disconnect the battery negative cable.

Look at the place the screw goes into. Is there a plastic ring or boss
around it, insulating the screw from the case of the machine? If so,
then it's NOT a ground wire, and you CANNOT safety wire it to anything
that is grounded.

Also, look to see how contact is made. There should be a ring terminal
on the end of the wire. If there is a fairly substantial ring of metal
on the machine under the ring terminal, such that it contacts all of the
ring terminal all around, then that's probably where most of the
electrical contact happens, and the screw threads are just there to hold
it down. (If not, see "A" below.) In this case, I would consider this:
Get an aircraft-approved screw with the same thread as the existing screw,
plus a hex (internal or external) head. Also get an aircraft-approved
flat washer that fits the screw. You'll also need some brake cleaner or
alcohol, the lowest grade of Loctite, something like a Q-tip, compressed
air, and maybe some masking tape. Loctite comes in different grades and
usually has a note like "can be disassembled with hand tools" or "must
use power tools and/or heat to disassemble" on the package. You want
the "hand tools" kind, which _will_ come apart when you want it to.

Make sure: master off, battery disconnected. Unscrew the existing
screw. Apply brake cleaner or alcohol to Q-tip and clean ring terminal
on both sides; let it dry. Apply brake cleaner or alcohol to a fresh
Q-tip and clean the screw threads; let it dry. If there is any
possibility at all that you will get liquid into the generator/alternator,
cover the holes with masking tape. Then put brake cleaner or alcohol on
a fresh Q-tip and clean the place where the ring terminal bolts down -
get down in the threads if at all possible. Let it dry for a few minutes,
then give a gentle quick shot of compressed air in the threads to make
sure it's dry. Assemble the washer onto the new screw (rounded edge away
from screw head), then put the screw+washer through the ring terminal.
Hold the screw+washer+terminal near the place it screws into, and apply
the tiniest drop of Loctite that you can to the screw threads. (It may
be helpful to put a drop of Loctite on a cleaned piece of solid wire,
safety pin, etc, and then use that to put the Loctite on the threads,
instead of trying to squeeze the Loctite directly onto the threads.)
Start installing the screw, being very careful not to get any Loctite
anywhere other than on the threads. If you get Loctite on the ring
terminal or on the place where the ring terminal seats, take it apart,
clean everything, and start over. Once the screw is finger tight, get
the proper wrench or Allen key and torque it to spec. Remove any masking
tape that was applied and reconnect the battery. Count your tools. Do
a test run.

A: On the other hand, if the underside of the ring terminal is not totally
in contact with metal, then some of the electrical contact may be taking
place on the threads and Loctite may not be advisable. The best answer
in this case is probably to install an approved lockwasher under the
screw head (it should go screw, lockwasher, ring terminal, machine),
torque to spec, and inspect regularly.

Disclaimer: This is based on experience with ground vehicles and by
looking at the generator setup on a 182. I don't have an A&P; I don't
even have a TG&Y. Some of this may not be allowable owner maintenance.
Some of this may not be allowable on a certificated aircraft. Your
mileage may vary.

Matt Roberds

Gig 601XL Builder
June 20th 07, 09:09 PM
wrote:
> I don't have an A&P; I don't
> even have a TG&Y.

OK how many hear understand the TG&Y reference?

For extra points what did it stand for?

flynrider via AviationKB.com
June 20th 07, 09:38 PM
Gig 601XL Builder wrote:
>> I don't have an A&P; I don't
>> even have a TG&Y.
>
>OK how many hear understand the TG&Y reference?
>
>For extra points what did it stand for?

Wasn't TG&Y a discount store? I remember them from the 60s/70s.

John Galban=====>N4BQ (PA28-180)

--
Message posted via http://www.aviationkb.com

Ross
June 20th 07, 10:01 PM
Mark Hansen wrote:
> On 06/20/07 08:54, Jay Honeck wrote:
>
> [ snip ]
>
>
>>Anyway, what should I put on this stupid screw to stop it from
>>vibrating loose? LocTite? Another lock washer? There's no way to
>>safety wire it...
>>
>>Thanks!
>
>
> Can you get a bolt/screw that will fit the threads and which can
> be safety wired? ... or would that not be an "approved" part?

I thought the retainer was a nut on the alternator. If you have enough
thread room (and a star washer is not doing the job) you could put a
second nut to be a jam nut.

--

Regards, Ross
C-172F 180HP
KSWI

Gig 601XL Builder
June 20th 07, 10:09 PM
flynrider via AviationKB.com wrote:
> Gig 601XL Builder wrote:
>>> I don't have an A&P; I don't
>>> even have a TG&Y.
>>
>> OK how many hear understand the TG&Y reference?
>>
>> For extra points what did it stand for?
>
> Wasn't TG&Y a discount store? I remember them from the 60s/70s.
>
> John Galban=====>N4BQ (PA28-180)


Right and now go fo the extra points.

Dan Luke
June 20th 07, 10:30 PM
"Gig 601XL Builder" wrote:

> OK how many hear understand the TG&Y reference?
>
> For extra points what did it stand for?

"Thimbles, Girdles & Yoyos"

Ross
June 20th 07, 10:36 PM
Dan Luke wrote:
> "Gig 601XL Builder" wrote:
>
>
>>OK how many hear understand the TG&Y reference?
>>
>>For extra points what did it stand for?
>
>
> "Thimbles, Girdles & Yoyos"
>
>
no TG&Y was a twentieth century five and dime or variety store chain in
the United States. The chain was named for founders Thomlinson, Gosselin
and Young.

--

Regards, Ross
C-172F 180HP
KSWI

Gig 601XL Builder
June 20th 07, 10:36 PM
Dan Luke wrote:
> "Gig 601XL Builder" wrote:
>
>> OK how many hear understand the TG&Y reference?
>>
>> For extra points what did it stand for?
>
> "Thimbles, Girdles & Yoyos"

Toys, Games & YoYos

Gig 601XL Builder
June 20th 07, 10:39 PM
Gig 601XL Builder wrote:
> Dan Luke wrote:
>> "Gig 601XL Builder" wrote:
>>
>>> OK how many hear understand the TG&Y reference?
>>>
>>> For extra points what did it stand for?
>>
>> "Thimbles, Girdles & Yoyos"
>
> Toys, Games & YoYos

I hit enter to quick.

Toys Games & YoYos is what we always heard it was as kids. I was somewhat
disheartend to later find out it was named after it founders Thomlinson,
Gosselin and Young.

Dan Luke
June 20th 07, 10:43 PM
"Ross" wrote:

>>
>>>OK how many hear understand the TG&Y reference?
>>>
>>>For extra points what did it stand for?
>>
>>
>> "Thimbles, Girdles & Yoyos"
> no TG&Y was a twentieth century five and dime or variety store chain in the
> United States. The chain was named for founders Thomlinson, Gosselin and
> Young.

Really?

Gosh!

Blueskies
June 21st 07, 12:44 AM
Purple 'small screw threadlocker' loctite would work great for this or similar applications. It is easily removable and
made for this purpose...


"RST Engineering" > wrote in message ...
> PLEASE, NO LOCTITE. LOCTITE MEANS THAT YOU NEVER WANT TO REMOVE THE SCREW AGAIN, which is going to play hell if the
> alternator itself ever craps out.
>
> If it is a bare wire, then no lockwasher in the world will help. Put a crimp terminal on the wire and then an INTERNAL
> TOOTH star or splitring lockwasher. The order of assembly is alternator, crimp terminal, lockwasher, screw.
>
> Jim
>

David Lesher
June 21st 07, 03:21 AM
(Jay Masino) writes:


>"Generally" there's only 2 wires on the alternator; the field wire from
>the regulator, and the output. Ground is usually established through
>the case of the alternator and associated bracket. If it was a
>relatively thin wire, it was more likely that it was the field. If
>that's the case, you defintely DON'T want to safety wire it. A fresh
>lock washer, and if you absolutely must, a very small dab of Locktite.


I disagree; many alternators I've seen have an added ground wire.
The engine sits on rubber motor mounts, you see...

Jac surely knows the difference between a wire screwed to the case;
and one going to a terminal...

Jay: I'm not thrilled with the locktite idea. Insulation is the last
thing you want & loctite is no conductor. You want a screwhead of some
kind that you can a) put new sharp-toothed lockwashers on. b) you can
safety wire down.

Now, where to find same is an exercise for the student....



--
A host is a host from coast to
& no one will talk to a host that's close........[v].(301) 56-LINUX
Unless the host (that isn't close).........................pob 1433
is busy, hung or dead....................................20915-1433

Jim Carter[_1_]
June 21st 07, 03:26 AM
Since the locktite (judiciously applied) will only be on the threads,
wouldn't the compression of the wire or eyelet between the alternator body
and the screw head provide enough conductivity?

--
Jim Carter
Rogers, Arkansas
"David Lesher" > wrote in message
...
> (Jay Masino) writes:
>
>
>>"Generally" there's only 2 wires on the alternator; the field wire from
>>the regulator, and the output. Ground is usually established through
>>the case of the alternator and associated bracket. If it was a
>>relatively thin wire, it was more likely that it was the field. If
>>that's the case, you defintely DON'T want to safety wire it. A fresh
>>lock washer, and if you absolutely must, a very small dab of Locktite.
>
>
> I disagree; many alternators I've seen have an added ground wire.
> The engine sits on rubber motor mounts, you see...
>
> Jac surely knows the difference between a wire screwed to the case;
> and one going to a terminal...
>
> Jay: I'm not thrilled with the locktite idea. Insulation is the last
> thing you want & loctite is no conductor. You want a screwhead of some
> kind that you can a) put new sharp-toothed lockwashers on. b) you can
> safety wire down.
>
> Now, where to find same is an exercise for the student....
>
>
>
> --
> A host is a host from coast to
> & no one will talk to a host that's close........[v].(301) 56-LINUX
> Unless the host (that isn't close).........................pob 1433
> is busy, hung or dead....................................20915-1433

Jay Masino
June 21st 07, 12:27 PM
David Lesher > wrote:
> I disagree; many alternators I've seen have an added ground wire.
> The engine sits on rubber motor mounts, you see...
>

Most aircraft have a heavy "battery cable" (for lack of a better
description) connecting the engine case to the airframe. Because of
this, the rubber lord mounts are generally irrelevent.

> Jay surely knows the difference between a wire screwed to the case;
> and one going to a terminal...
>

Not necessarily.


--- Jay


--

Jay Masino "Home is where My critters are"
http://www.JayMasino.com
http://www.OceanCityAirport.com
http://www.oc-Adolfos.com

David Lesher
June 21st 07, 05:18 PM
"Jim Carter" > writes:

>Since the locktite (judiciously applied) will only be on the threads,
>wouldn't the compression of the wire or eyelet between the alternator body
>and the screw head provide enough conductivity?

Your belief in the ability to control the locktite's meandering exceeds
mine...
--
A host is a host from coast to
& no one will talk to a host that's close........[v].(301) 56-LINUX
Unless the host (that isn't close).........................pob 1433
is busy, hung or dead....................................20915-1433

David Lesher
June 21st 07, 05:41 PM
(Jay Masino) writes:

>> I disagree; many alternators I've seen have an added ground wire.
>> The engine sits on rubber motor mounts, you see...

>Most aircraft have a heavy "battery cable" (for lack of a better
>description) connecting the engine case to the airframe. Because of
>this, the rubber lord mounts are generally irrelevent.

So do cars, but.... The only grounds you KNOW will never vibrate loose,
get corroded, you name it.. are the ones that don't exist.

The alternator is bolted down to the block, surely that's good enough,
right? May I introduce you to a gentleman named Murphy?

A classic Car-Talk "stump the chumps" type question involved now-25+yo
MOPARs. [Think fully size Plymouth Fury, etc.]

Why do the headlights get BRIGHTER when you step on the clutch or the
brakes? The engine-to-frame bond was failing. The drivetrain was mostly
isolated by rubber mounts BUT the clutch fork etc. was a substitute
path. Applying the brakes made drum contact and there was a parking brake
cable, you see... I've even heard that the current through same would eat
the driveshaft U-joint bearings.

The alternator noise he described is symptomatic of two possible causes:

a) Bad alternator diodes.

b) ground grief: either a missing one, or an added one in a audio circuit
[aka ground loop].

I always think "grounds" first thing when some talks of noise...



>> Jay surely knows the difference between a wire screwed to the case;
>> and one going to a terminal...

>Not necessarily.

Well, I'll keep my faith in him for now.


[Do aircraft installations of his vintage even use screw terms for
field/aux alternator connections? Autos have used latched plugs for
decades with only the large high current output wire being a stud &
lug...]


--
A host is a host from coast to
& no one will talk to a host that's close........[v].(301) 56-LINUX
Unless the host (that isn't close).........................pob 1433
is busy, hung or dead....................................20915-1433

Jay Masino
June 21st 07, 06:34 PM
David Lesher > wrote:
> [Do aircraft installations of his vintage even use screw terms for
> field/aux alternator connections? Autos have used latched plugs for
> decades with only the large high current output wire being a stud &
> lug...]


It's a screw terminal.

--- Jay



--

Jay Masino "Home is where My critters are"
http://www.JayMasino.com
http://www.OceanCityAirport.com
http://www.oc-Adolfos.com

RST Engineering
June 21st 07, 06:53 PM
You will find that most modern aircraft designs and installations are the
best that 1940s technology can provide.

Jim

--
"Dream as if you'll live forever. Live as if you'll die today."
--James Dean



> David Lesher > wrote:
>> [Do aircraft installations of his vintage even use screw terms for
>> field/aux alternator connections? Autos have used latched plugs for
>> decades with only the large high current output wire being a stud &
>> lug...]

Capt. Geoffrey Thorpe
June 21st 07, 11:26 PM
"RST Engineering" > wrote in message
...
> PLEASE, NO LOCTITE. LOCTITE MEANS THAT YOU NEVER WANT TO REMOVE THE SCREW
> AGAIN, which is going to play hell if the alternator itself ever craps
> out.
>

I've put a lot of loctite on a lot of phillips head screws - and they come
out just fine. In fact, in wet environments where you have steel screws in
aluminium parts, they come out easier with loctite because it tends to seal
the threads and reduce corrosion.

Note: Use the right grade of thread lock...

--
Geoff
The Sea Hawk at Wow Way d0t Com
remove spaces and make the obvious substitutions to reply by mail
When immigration is outlawed, only outlaws will immigrate.

Ray Andraka
June 27th 07, 10:41 PM
Mark Hansen wrote:

> On 06/20/07 08:54, Jay Honeck wrote:
>
> [ snip ]
>
>
>>Anyway, what should I put on this stupid screw to stop it from
>>vibrating loose? LocTite? Another lock washer? There's no way to
>>safety wire it...
>>
>>Thanks!
>
>
> Can you get a bolt/screw that will fit the threads and which can
> be safety wired? ... or would that not be an "approved" part?

Yeah, that's a great idea. Safety wire the field terminal to ground.
Might keep the nut from loosening up, but I'll bet your voltage
regulator won't like the resulting short to ground much.

Mark Hansen
June 27th 07, 10:55 PM
On 06/27/07 14:41, Ray Andraka wrote:
> Mark Hansen wrote:
>
>> On 06/20/07 08:54, Jay Honeck wrote:
>>
>> [ snip ]
>>
>>
>>>Anyway, what should I put on this stupid screw to stop it from
>>>vibrating loose? LocTite? Another lock washer? There's no way to
>>>safety wire it...
>>>
>>>Thanks!
>>
>>
>> Can you get a bolt/screw that will fit the threads and which can
>> be safety wired? ... or would that not be an "approved" part?
>
> Yeah, that's a great idea. Safety wire the field terminal to ground.
> Might keep the nut from loosening up, but I'll bet your voltage
> regulator won't like the resulting short to ground much.

Was the sarcasm really necessary Ray? I assumed the OP would know
whether or not safety wire could be used in such a case.


--
Mark Hansen, PP-ASEL, Instrument Airplane, USUA Ultralight Pilot
Cal Aggie Flying Farmers
Sacramento, CA

Ray Andraka
June 27th 07, 11:27 PM
Mark Hansen wrote:

>
> Was the sarcasm really necessary Ray? I assumed the OP would know
> whether or not safety wire could be used in such a case.
>
>
No, I suppose not. Long day (I know, no excuse).

Mark Hansen
June 27th 07, 11:55 PM
On 06/27/07 15:27, Ray Andraka wrote:
> Mark Hansen wrote:
>
>>
>> Was the sarcasm really necessary Ray? I assumed the OP would know
>> whether or not safety wire could be used in such a case.
>>
>>
> No, I suppose not. Long day (I know, no excuse).

Well ... I was going to say that it didn't sound like you ;-)
Let's forget it.

Best Regards,

Jay Honeck
June 29th 07, 10:13 PM
> > No, I suppose not. Long day (I know, no excuse).
>
> Well ... I was going to say that it didn't sound like you ;-)
> Let's forget it.

Besides -- maybe I *like* a short to ground -- d'ja ever think of
THAT?

:-)

Follow up: Although the whine is better now, after tightening the
screw, it's still there in the background.

Gotta keep looking, I guess.
--
Jay Honeck
Iowa City, IA
Pathfinder N56993
www.AlexisParkInn.com
"Your Aviation Destination"

John[_9_]
July 11th 07, 03:26 PM
On Jun 20, 11:54 am, Jay Honeck > wrote:
> When we flew our '75 Warrior, it developed a problem with the
> alternator going off-line in flight. This was preceeded by the
> ammeter needle bouncing crazily and finally pegging at 60 amps.
>
> I fixed that problem by spending an hour tracing all the electrical
> lines, and tightening connections. The main culprit was a wire
> connector that was screwed into the backside of the alternator with a
> simple phillips screw -- no safety wire, no loc-tite, no nuthin'.
> Looked like a ground wire to me, but I'm no mechanic.
>
> I turned it a good two and half turns, and the problem went away,
> never to return. We sold the plane in '02.
>
> Recently, Atlas developed a nasty, annoying whine in the headphones.
> This developed immediately after I had removed the PS Engineering CD/
> Intercom for some panel maintenance, so I naturally assumed that they
> were related.
>
> No amount of re-seating, cleaning, wiggling had any effect. My
> frustration was mounting.
>
> Then, this past Sunday, I decided to chang the oil after our return
> flight from the Cherokee Pilots Association fly-in. It was Fathers
> Day, it was 100 degrees in the hangar, and we were both melting, but I
> decided to de-cowl the plane in order to make the oil change easier,
> and to trace the wiring -- just in case it was another loose
> connection somewhere.
>
> Of course, the first place I looked was the backside of the
> alternator, and, lo and behold, the same damned wire was loose! A
> few turns to tighten, and voila! -- no more whine. (I traced the rest
> of the wiring, while I was at it, and found a couple of broken zip
> ties, and one broken wire -- a lead going to one of my cylinder
> heaters. It's broken right where it goes into the cylinder -- THAT
> looks like absolutely no fun to repair...)
>
> Anyway, what should I put on this stupid screw to stop it from
> vibrating loose? LocTite? Another lock washer? There's no way to
> safety wire it...
>
> Thanks!
> --
> Jay Honeck
> Iowa City, IA
> Pathfinder N56993www.AlexisParkInn.com
> "Your Aviation Destination

The wiring diagram shows a three wire set up. Field, Batt. and
Ground. Field and Battery or A+ are going to be studs with nuts.
Your screw into the case is apparently the ground connection for the
alternator and a good choice for a noise in the headsets complaint.
The noise could still be a bad diode but a poor ground would only
exacerbate it. A good quality lock washer under the head of the screw
is essential shop practice in this case. There are different grades
of lock tite including removeable (go figure). You want to avoid
getting lock tite on the mating surfaces of the screw, washers and
terminal ends to avoid inadvertently insulating them.

John Dupre'

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