Different plane, same fix

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

"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

(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

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

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...]

"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.

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.

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

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).

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,