Today's Message Index:
----------------------
1. 07:08 AM - Re: Re: Radios OFF during startup (Brian Lloyd)
2. 08:42 AM - Re: Why use starter contactor? ()
3. 08:43 AM - Re: Radios OFF during startup (Robert L. Nuckolls, III)
4. 09:12 AM - Visio symbols (tom)
5. 09:43 AM - Re: Visio symbols (Lloyd, Daniel R.)
6. 11:30 AM - Air Speed Switch (dsvs@comcast.net)
7. 01:01 PM - Re: Visio symbols (Mickey Coggins)
8. 02:51 PM - Re: Re: Why use starter contactor? (John D. Heath)
9. 02:51 PM - Re: Glide Slope Antenna (Richard Dudley)
10. 02:53 PM - Re: Re: Why use starter contactor? (Robert L. Nuckolls, III)
11. 03:02 PM - Re: Radios OFF during startup (Robert L. Nuckolls, III)
12. 03:08 PM - Re: Re: Why use starter contactor? (Robert L. Nuckolls, III)
13. 04:02 PM - Re: Re: Why use starter contactor? (Brian Lloyd)
14. 04:22 PM - Re: Checking out a radio installation (Steven Anderson)
15. 04:41 PM - Re: Re: Why use starter contactor? (Brian Lloyd)
16. 08:01 PM - Re: Re: Why use starter contactor? (Robert L. Nuckolls, III)
Message 1
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| Subject: | Re: Radios OFF during startup |
--> AeroElectric-List message posted by: Brian Lloyd <brian-yak@lloyd.com>
Robert L. Nuckolls, III wrote:
> --> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
>
> At 06:19 PM 4/6/2006 -0500, you wrote:
>
>> --> AeroElectric-List message posted by: "Dave Morris \"BigD\""
>> <BigD@DaveMorris.com> Learned] Radios OFF during startup
>>
>> I guess that would mean that the $150 radio in my car is more robust
>> than the $3,500 radio in your airplane? I sure don't have an
>> avionics master switch in my car.
>>
>> Dave Morris
>
>
> Good question. The avionics master switch is still alive
> and well in many venues but nobody I've come across can
> explain the science or describe the repeatable experiment
> that shows why it's 'needed'.
Oh, that one is easy Bob. It is convenient. Some aircraft have a LOT of
radios. My aztec has an audio panel, a GPS/comm, a nav-com, an RNAV
receiver, an ADF, a transponder, an EHSI, a horizontal gyro (separate
circuit from the EHSI, and a music radio. It is a pain the butt to turn
all those on/off switches. It is much more convenient to have one switch
to turn all that stuff on and off. Of course, that one switch can also
turn all that stuff off at the same time when I don't want it to.
When I did the e-bus in my Comanche 20 years ago I added a second switch
that would connect my e-bus (I called it the avionics bus then but it
also had the needle-ball on it too) to the backup battery in case the
main avionics bus switch failed. (At the time it was a SPDT center-off
switch -- yeah, I have learned something since then.)
--
Brian Lloyd 361 Catterline Way
brian-yak at lloyd dot com Folsom, CA 95630
+1.916.367.2131 (voice) +1.270.912.0788 (fax)
I fly because it releases my mind from the tyranny of petty things . . .
- Antoine de Saint-Exupery
Message 2
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| Subject: | Re: Why use starter contactor? |
--> AeroElectric-List message posted by: <gmcjetpilot@yahoo.com>
>From: Ken <klehman@albedo.net>
>Subject: Re: Why use starter contactor?
>Possibly because the pros and cons of that have been discussed at length
>several times here Michael. Several folks related experiences with stuck
>on automotive starters when I've brought up the subject. Nevertheless I
>went with a 25 amp rated marine key starter switch which I believe is
>less likely to cause problems than an additional small relay. A cheap 40
>amp relay is not immune from sticking either in this kind of service. Got
>to admit though my key switch will be a bear to change out compared to a
>contactor or a small relay when/if it ever fails, and it cost more than
>either.
>Ken
Ken:
Thanks for the thoughtful reply.
My postulation is if you use a BIG FAT start button and no extra firewall relay/
solenoids/contactors, chance of starter run-on / spontaneous engagement is nil.
Has this happened in a car you know of? To the config I suggest in a plane?
Your comment about *several folks* who claim they had problems is great, but
with out details its like the OV alternator thing, just rumor or irrelevant.
There are reasons a starter can run-on. I suspect you are either talking a
old Bendix drive starters or OLD firewall Cessna or Piper firewall solenoids,
which do stick when they get old. Neither apply to our conversation.
People who switched to new starters have got run-ons because the OLD firewall
solenoid was retained and stuck; its NOT an issue of the starter itself.
This supports my claim that LESS IS MORE. Get rid of that old solenoid and
get a big 60 amp start button.
I researched this thoroughly. I talked to SkyTec. The chance of sticking starter
is next to nothing. I also asked about the no secondary solenoid and guess
what? They said its made that way and will work fine. Let's say you did get
a run-on, it would be during start, you would shut down. SkyTec shows how
to wire a run-on light if you like. Chance of it engaging in flight? never.
Skytec has more starters flying than anyone. I think they know what's up.
QUOTE:
What about the Bendix? Maybe it stuck?
**Since Sky-Tec starters do not use mechanical Bendix drives to actuate the
starter, this is actually nearly impossible for a Sky-Tec starter to keep itself
engaged with the aircraft ring gear. Sky-Tec starters are electromechanically
engaged therefore requiring voltage to engage the starter's drive pinion gear with
the ring gear. Without voltage, the pinion simply cannot remain in the flywheel.
A spring and a helical return will both force the drive pinion back out of the
ring
gear and into the rest position.**
Ref: http://www.skytecair.com/Cessna_Solenoids.htm
Cessna (mostly) and Piper, apparently have a history of Firewall Solenoids
sticking, so actually even a factory solenoid (relay) can stick. That is WHY
I suggest a big OLD fat start button, like a race car. (w/ catch diode of course)
All the $60,000-$200,000 Luxury and Sport cars are going to no key push
button start switches.
Here is some other good info from SkyTec:
Troubleshooting Diagram: guide to Gen & spacific (to run on) issues:
http://www.skytecair.com/Troubleshooting.htm
Here is two wiring diagrams from SkyTec:
http://www.skytecair.com/Wiring_diag.htm
Here is a guide to wiring, with specifics to starters:
http://www.skytecair.com/Wiring_Experimental.pdf
To be fair to Bob, if it ain't broke don't fix it. Nothing WRONG with the
Z diagram xyz, just suggesting if you want a lean mean electrical system
with more than adequate or even superior reliability and safety, while
lowering weight and complexity, consider trashing the BIG fw contactor.
The next step is get rid of the BIG master contactor. You only need a
30-60 amp relay if you don't run the starter load through it.
Cheers George
---------------------------------
Message 3
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| Subject: | Radios OFF during startup |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
At 09:36 PM 4/6/2006 -0700, you wrote:
>--> AeroElectric-List message posted by: "B Tomm" <fvalarm@rapidnet.net>
>
>Is it possible that the radio was somehow affected by a short duration "low"
>voltage as the engine drew massive current during start?
>
>Bevan
If that's the real cause, then the device has some serious deficiencies. Here's
a piece I did on DO-160 testing some years ago for a builder and updated this
morning for posting on my website at:
http://www.aeroelectric.com/articles/What's_all_this_DO160_Stuff_Anyhow.pdf
See paragraph (c)
Bob . . .
< What is so wonderful about scientific truth...is that >
< the authority which determines whether there can be >
< debate or not does not reside in some fraternity of >
< scientists; nor is it divine. The authority rests >
< with experiment. >
< --Lawrence M. Krauss >
Message 4
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--> AeroElectric-List message posted by: "tom" <kesleyel@iowatelecom.net>
I am using Microsoft Visio for the drawings of my electrical system. While
creating the symbols is fairly straightforward, I have not yet discovered
how to place the small blue "x" connection points where I need them. The
basic shapes come with them, but I need to place them at the end of a line,
such as a diode symbol. Also, how are the unneeded ones deleted when the
symbol is complete? Any help much appreciated.
Tom Barter
Kesley, IA
Avid Magnum O-320
Message 5
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--> AeroElectric-List message posted by: "Lloyd, Daniel R." <LloydDR@wernerco.com>
You can take a standard template drawing and modify it by using the un
group function and it will become a series of shapes, take one of the
templates, ungroup it, copy the item you want and re-group the template
and paste the copy into your item.
Hope it helps
Do not archive
Dan
RV10 4269
-----Original Message-----
From: owner-aeroelectric-list-server@matronics.com
[mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of tom
Sent: Friday, April 07, 2006 12:10 PM
Subject: AeroElectric-List: Visio symbols
--> AeroElectric-List message posted by: "tom"
<kesleyel@iowatelecom.net>
I am using Microsoft Visio for the drawings of my electrical system.
While
creating the symbols is fairly straightforward, I have not yet
discovered
how to place the small blue "x" connection points where I need them.
The
basic shapes come with them, but I need to place them at the end of a
line,
such as a diode symbol. Also, how are the unneeded ones deleted when
the
symbol is complete? Any help much appreciated.
Tom Barter
Kesley, IA
Avid Magnum O-320
Message 6
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| Subject: | Air Speed Switch |
--> AeroElectric-List message posted by: dsvs@comcast.net
Bob and Others
I need to purchase an airspeed switch that is closed when stationary and opens
at roughly 15 knots. An adjustable unit is fine as long as the adjustment point
can be set for fairly low (15-20 knot) range. Any idea of a vendor for this
device. ACS has only one and the adjustment point is above 80 knots. Thanks
in advance. Don
Message 7
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| Subject: | Re: Visio symbols |
--> AeroElectric-List message posted by: Mickey Coggins <mick-matronics@rv8.ch>
> I am using Microsoft Visio for the drawings of my electrical system. While
> creating the symbols is fairly straightforward, I have not yet discovered
> how to place the small blue "x" connection points where I need them. The
> basic shapes come with them, but I need to place them at the end of a line,
> such as a diode symbol. Also, how are the unneeded ones deleted when the
> symbol is complete? Any help much appreciated.
Hi Tom,
I think this article will help you out.
http://www.2000trainers.com/printarticle.aspx?articleID=206
--
Mickey Coggins
http://www.rv8.ch/
#82007 finishing
Message 8
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| Subject: | Re: Why use starter contactor? |
--> AeroElectric-List message posted by: "John D. Heath" <altoq@cebridge.net>
TWIMC (Which is probaly only me),
(1) Electrial Solenoid engaged starters,as used on Lycoming, Chevrolet,BMW,
and Porsche, do stick.
(2) Solenoid engaged starters are disengaged by a spring and an over running
mechanism in the starter gear.
(3) I have personally seen three out of the four named, stick .
(4) They stick and continue to crank the engine, they stick and don't crank
the engine, and all modes of stick in between.
(5) They stick when they are new or old, clean or dirty but mostly they
stick because they are misaligned or have not been lubricated.
(6) One of these starters that fail in the "CRANK the engine mode" with the
+12VDC wired directly to the solenoid has a great big wire as big around as
your index finger HOT and you can't turn it off.
(7) There are many light weight relays capable of eliminating this problem
by attaching the +12VDC first to it and then on to the starter solenoid. No
device that controls the starter directly through its solenoid control
circuit can do this.
(8) I have had multiple experiences with these type failures. Allow me to
pass these experiences on to you and eliminate the time and aggravation it
would take for you to accumulate them yourself. Use the information as you
will.
(9) DO NOT ARCHIVE
John D.
Message 9
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| Subject: | Re: Glide Slope Antenna |
--> AeroElectric-List message posted by: Richard Dudley <rhdudley@att.net>
Thanks, Bob.
RHDudley
Robert L. Nuckolls, III wrote:
>--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
>
>At 04:20 PM 4/5/2006 -0400, you wrote:
>
>
>
>>--> AeroElectric-List message posted by: Richard Dudley <rhdudley@att.net>
>>
>>Hi Bob,
>>Where would I find the GS antenna diagram that is referred to here?
>>
>>
>
> The diagram we've been discussing is Figure 13-13 in the
> 'Connection. Finding someplace to mount such a beast is the
> hard part. I think I'd go for the coupler approach. Or, if
> you have a fiberglass airplane, try sticking an 8" piece of wire
> into a BNC connector and let it dangle out the back of the
> GS receiver. When on the runway centerline, glideslope and
> localizer signals are huge. You're looking right down the
> "barrel" of a 5w transmitter from a couple miles away max.
> A wet string would probably get you a good enough signal.
>
>
> If a compromise antenna doesn't work, go for the coupler
> from http://www.chiefaircraft.com and others. Looks
> like this:
>
>http://www.aeroelectric.com/Pictures/Antenna/CI_507.jpg
>
> I'd much rather install a coupler somewhere than try
> to find a 'nice' place to mount a stand-alone GS
> antenna.
>
> Bob . . .
>
>
>
>
>
>
>
>
>
>
Message 10
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| Subject: | Re: Why use starter contactor? |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
At 08:37 AM 4/7/2006 -0700, you wrote:
>--> AeroElectric-List message posted by: <gmcjetpilot@yahoo.com>
>
> >From: Ken <klehman@albedo.net>
> >Subject: Re: Why use starter contactor?
>
> >Possibly because the pros and cons of that have been discussed at
> length
> >several times here Michael. Several folks related experiences with
> stuck
> >on automotive starters when I've brought up the subject.
> Nevertheless I
> >went with a 25 amp rated marine key starter switch which I believe is
> >less likely to cause problems than an additional small relay. A
> cheap 40
> >amp relay is not immune from sticking either in this kind of
> service. Got
> >to admit though my key switch will be a bear to change out
> compared to a
> >contactor or a small relay when/if it ever fails, and it cost more
> than
> >either.
> >Ken
>
> Ken:
>
> Thanks for the thoughtful reply.
>
> My postulation is if you use a BIG FAT start button and no extra
> firewall relay/
>solenoids/contactors, chance of starter run-on / spontaneous engagement is
>nil.
>
>Has this happened in a car you know of? To the config I suggest in a plane?
>
> Your comment about *several folks* who claim they had problems is
> great, but
>with out details its like the OV alternator thing, just rumor or irrelevant.
Wasn't rumor. Had many customers report the phenomenon and we demonstrated
it on the bench . . .
>
>
> There are reasons a starter can run-on. I suspect you are either talking a
>old Bendix drive starters or OLD firewall Cessna or Piper firewall solenoids,
>which do stick when they get old. Neither apply to our conversation.
Nope, we were talking about modern PM starters . . .
>
> People who switched to new starters have got run-ons because the OLD
> firewall
>solenoid was retained and stuck; its NOT an issue of the starter itself.
>
> This supports my claim that LESS IS MORE. Get rid of that old solenoid and
>get a big 60 amp start button.
Not so. "Run on" in the context of PM starters and airplanes had
nothing to do with the selection of contactors.
Unlike wound-field motors supplied on B&C (and perhaps other)
starters, the PM offerings by Skytec (and perhaps others) are
efficient GENERATORS of electrical power while the armatures are
spinning down. When the pilot releases the starter button after
the engine fires, connection between the starter motor and battery
was being opened just fine. However, IF the starter was wired for
external contactor, voltage being generated by the coasting armature
was still applied to the solenoid engagement windings thus keeping
the pinion gear engaged for some period of time (perhaps 2-5 seconds)
after the button was released. The starter's overrun clutch prevented
damage but it was obviously an undesirable operating quality.
One fix was to go to Figure Z-22 such that the starter's built
in contactor became the primary electrical switching device. The relay
allowed any starter switch selected by the builder to stay in place.
Adding the relay broke power to the solenoid's hold-coil and effected
immediate release of the pinion gear in spite of the armature's
spin-down voltage. Another option was described in October of 2004
when this sketch was published on my website:
http://www.aeroelectric.com/articles/StarterWiring.pdf
Figure 3 suggests using the "I" terminal of the external contactor
to exert absolute control over the solenoid's hold coil.
Of course, the forth options is Figure 1, a 30A push button and
14AWG wire to replace the relay shown in Z-22 for what has been
described as the simplest approach. This approach is also electrically
acceptable but offers the least number of options for selection
of start switches. The "run-on" or delayed disengagement phenomenon
is unique to PM starters and has nothing to do with sticking contactors.
>
>
>I researched this thoroughly. I talked to SkyTec. The chance of sticking
>starter
>is next to nothing.
But not zero . . .
> I also asked about the no secondary solenoid and guess
>what? They said its made that way and will work fine. Let's say you did get
>a run-on, it would be during start, you would shut down. SkyTec shows how
>to wire a run-on light if you like. Chance of it engaging in flight? never.
>
> Skytec has more starters flying than anyone. I think they know what's up.
Yup, ask them about sticking contactors and they can accurately
report no big problems as will every other starter manufacturer.
Ask them about delayed disengagement or run-on of their starters
when wired like B&C starters, and they'll confirm what I've stated
above.
No rumors, hard repeatable experiments.
>
>
> QUOTE:
>
> What about the Bendix? Maybe it stuck?
>
>**Since Sky-Tec starters do not use mechanical Bendix drives to actuate the
>starter, this is actually nearly impossible for a Sky-Tec starter to keep
>itself
>engaged with the aircraft ring gear. Sky-Tec starters are
>electromechanically
>engaged therefore requiring voltage to engage the starter's drive pinion
>gear with
>the ring gear. Without voltage, the pinion simply cannot remain in the
>flywheel.
>A spring and a helical return will both force the drive pinion back out of
>the ring
>gear and into the rest position.**
This is true of every brand of starter using direct engagement of the
pinion gear by a solenoid that also happens to drive a set of contacts for
control of armature current.
>
> Ref: http://www.skytecair.com/Cessna_Solenoids.htm
>
>
> Cessna (mostly) and Piper, apparently have a history of Firewall Solenoids
>sticking, so actually even a factory solenoid (relay) can stick. That is WHY
>I suggest a big OLD fat start button, like a race car. (w/ catch diode of
>course)
The sticking contactors on production airplanes is a well known
phenomenon when OEM's were using the intermittent duty versions
of the RBM/White-Rogers/Stancore contactors. These looked
just like the battery contactor shown at:
http://www.aeroelectric.com/Pictures/Contactors/s701-1.jpg
These contactors had large area, low pressure contacts
like:
http://www.aeroelectric.com/Pictures/Contactors/S701-1a.jpg
http://www.aeroelectric.com/Pictures/Contactors/S701-1b.jpg
. . . not the best way to control high inrush devices like
starters. In later years, the car guys showed us small-area,
high-pressure intermittent duty contactors like:
http://www.aeroelectric.com/Pictures/Contactors/s702-1l.jpg
http://www.aeroelectric.com/Pictures/Contactors/S702-1a.jpg
Contactor sticking was virtually eliminated for systems
where the battery was kept in good shape. The only cases
we've seen where an owner was able to weld a small-area,
high-pressure contactor was with a soggy battery that
barely managed to get the contactor closed but with
insufficient pressure to get good conduction, hence burned
and welded contacts.
We've seen starters wired with the big fat push button
(or Z-22 relay) weld the built-in contacts too. If the
battery is soggy or the engagement signal to the contactor
is tentative, welding risks go up markedly IRRESPECTIVE of
who's contactor is doing what to who's starter. I've had
several builders report this phenomenon where rapping the
contactor housing on the side of the starter with a
screwdriver handle would cause it to become unstuck.
>
>
>To be fair to Bob, if it ain't broke don't fix it. Nothing WRONG with the
>Z diagram xyz, just suggesting if you want a lean mean electrical system
>with more than adequate or even superior reliability and safety, while
>lowering weight and complexity, consider trashing the BIG fw contactor.
To be fair to me or anyone else, we need to be talking about
the same problem. The run-on problem described was identified
in a timely manner, demonstrated, explained, and fixed. It
had nothing to do with sticking contactors and was unique to
PM starters.
The sticking contactors of an earlier design was tolerated for
decades (from about 1946 through the mid 70's) because when a starter
contactor did stick, it was backed up by the battery master contactor.
While every airplane using the old style starter contactor suffered
the phenomenon, it wasn't a big deal. When the automotive designers
crafted the high-pressure design, it was welcomed by all.
> The next step is get rid of the BIG master contactor. You only need a
> 30-60 amp relay if you don't run the starter load through it.
Anyone is completely free to get rid of any parts they wish
and indeed many builders have done just that. The only thing
I'll suggest is that the decisions to do so exploit
the experience and thought processes behind 60+ years
aircraft electrical systems. An accurate sense of history
combined with an understanding of applicable simple-ideas helps us avoid
potentially unhappy and unintended consequences of "the next step."
If you're ready to hang your hat on an always hot, fat
feeder from battery to starter mounted contactor/solenoid,
keep in mind that the starter's built-in contactor can stick
too. Further, you loose pilot control over making the airplane's
electrical system max-cold. If those design goals are acceptable
then so be it. It's your airplane and it's experimental.
Fly in peace.
Bob . . .
Message 11
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| Subject: | Radios OFF during startup |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
Some folks have reported problems with their email clients recognizing
the address for the piece on DO-160 due to punctuation in the file title.
I've revised the file name and reposted at:
http://www.aeroelectric.com/articles/Whats_all_this_DO160_Stuff_Anyhow.pdf
Bob . . .
< What is so wonderful about scientific truth...is that >
< the authority which determines whether there can be >
< debate or not does not reside in some fraternity of >
< scientists; nor is it divine. The authority rests >
< with experiment. >
< --Lawrence M. Krauss >
Message 12
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| Subject: | Re: Why use starter contactor? |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
John,
Thank you for sharing this info. It tracks with what we understand
about the huge list of variables that affect starter and associated
contactor performance. Bottom line is that ALL starters of ANY brand
are subject to undesirable behavior for a host of reasons. None
of these events needs to be more than a frustrating maintenance item
if we leave certain "Plan-B" options in place for dealing with them
if and when they arise.
Bob . . .
At 04:47 PM 4/7/2006 -0500, you wrote:
>--> AeroElectric-List message posted by: "John D. Heath" <altoq@cebridge.net>
>
> TWIMC (Which is probaly only me),
>
>(1) Electrial Solenoid engaged starters,as used on Lycoming, Chevrolet,BMW,
>and Porsche, do stick.
>
>(2) Solenoid engaged starters are disengaged by a spring and an over running
>mechanism in the starter gear.
>
>(3) I have personally seen three out of the four named, stick .
>
>(4) They stick and continue to crank the engine, they stick and don't crank
>the engine, and all modes of stick in between.
>
>(5) They stick when they are new or old, clean or dirty but mostly they
>stick because they are misaligned or have not been lubricated.
>
>(6) One of these starters that fail in the "CRANK the engine mode" with the
>+12VDC wired directly to the solenoid has a great big wire as big around as
>your index finger HOT and you can't turn it off.
>
>(7) There are many light weight relays capable of eliminating this problem
>by attaching the +12VDC first to it and then on to the starter solenoid. No
>device that controls the starter directly through its solenoid control
>circuit can do this.
>
>(8) I have had multiple experiences with these type failures. Allow me to
>pass these experiences on to you and eliminate the time and aggravation it
>would take for you to accumulate them yourself. Use the information as you
>will.
Message 13
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| Subject: | Re: Why use starter contactor? |
--> AeroElectric-List message posted by: Brian Lloyd <brian-yak@lloyd.com>
Robert L. Nuckolls, III wrote:
> Unlike wound-field motors supplied on B&C (and perhaps other)
> starters, the PM offerings by Skytec (and perhaps others) are
> efficient GENERATORS of electrical power while the armatures are
> spinning down. When the pilot releases the starter button after
> the engine fires, connection between the starter motor and battery
> was being opened just fine. However, IF the starter was wired for
> external contactor, voltage being generated by the coasting armature
> was still applied to the solenoid engagement windings thus keeping
> the pinion gear engaged for some period of time (perhaps 2-5 seconds)
> after the button was released. The starter's overrun clutch prevented
> damage but it was obviously an undesirable operating quality.
I found this problem another way. After installation of one of these PM
starters my Comanche got hard to start when warm where it hadn't been
before. I didn't notice because at the time my father was flying it more
than I was and had several incidents of almost running the battery down
trying to start the engine when it was hot (carbureted engine, not fuel
injection). This was doubly surprising as the engine was equipped with a
shower of sparks ignition system. It would fire but then wouldn't
'catch' and keep running when the start button was released. The engine
would spin down and seem to 'catch' just before it quit turning. It was
very perplexing.
(You have enough information to solve this puzzle but just for fun I
will post the real problem and the fix in the next message so you can
think about it for just a moment.)
--
Brian Lloyd 361 Catterline Way
brian-yak at lloyd dot com Folsom, CA 95630
+1.916.367.2131 (voice) +1.270.912.0788 (fax)
I fly because it releases my mind from the tyranny of petty things . . .
- Antoine de Saint-Exupery
Message 14
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| Subject: | Re: Checking out a radio installation |
--> AeroElectric-List message posted by: "Steven Anderson" <s_s_and@hotmail.com>
I am at the stage where I want to make sure my radios and nav work before I
put on the panel that makes getting at all my wiring and radio stack very
difficult. In other words, I am at my garage and not near an airport.
I want to order a hand held nav/com to test my Garmin SL 30. Is there a set
procedure for this kind of thing. Can I just transmit on some obscure
frequency and try and receive on the other?
Thanks in Advance.
Do not archive
Steve Anderson
RV 7A
Message 15
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| Subject: | Re: Why use starter contactor? |
--> AeroElectric-List message posted by: Brian Lloyd <brian-yak@lloyd.com>
OK, where was I ... oh yeah, the hard starting Comanche after installing
a PM starter.
It seems that someone had wired the start lead to the shower-of-sparks
system to the starter side of the start solenoid. When the start button
was release the EMF generated by the still-turning PM starter would hold
the shower-of-sparks relay in and that would continue to disable the
right mag and keep the left mag on the retard breaker but it wouldn't
provide enough voltage to get the shower-of-sparks vibrator to really do
its thing. When cold the engine would freewheel better when the start
button was released and the shower-of-sparks start relay would drop out
before the engine lost too much RPM and it would start fine.
When trying to start after just a bit of a cool down the engine was
extra tight and would not freewheel so the engine spun down before the
starter did.
The solution? Move the start lead for the shower-of-sparks system from
the starter side of the solenoid to the start button itself. Now the
power went away instantly when the start button was released and the
engine would catch and run just fine.
BTW, this problem drove me nuts for about 6 months until I finally
figured it out.
--
Brian Lloyd 361 Catterline Way
brian-yak at lloyd dot com Folsom, CA 95630
+1.916.367.2131 (voice) +1.270.912.0788 (fax)
I fly because it releases my mind from the tyranny of petty things . . .
- Antoine de Saint-Exupery
Message 16
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| Subject: | Re: Why use starter contactor? |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
Isn't it amazing how those simple-ideas stack up sometimes?
Bob . . .
At 04:40 PM 4/7/2006 -0700, you wrote:
>--> AeroElectric-List message posted by: Brian Lloyd <brian-yak@lloyd.com>
>
>OK, where was I ... oh yeah, the hard starting Comanche after installing
>a PM starter.
>
>It seems that someone had wired the start lead to the shower-of-sparks
>system to the starter side of the start solenoid. When the start button
>was release the EMF generated by the still-turning PM starter would hold
>the shower-of-sparks relay in and that would continue to disable the
>right mag and keep the left mag on the retard breaker but it wouldn't
>provide enough voltage to get the shower-of-sparks vibrator to really do
>its thing. When cold the engine would freewheel better when the start
>button was released and the shower-of-sparks start relay would drop out
>before the engine lost too much RPM and it would start fine.
>
>When trying to start after just a bit of a cool down the engine was
>extra tight and would not freewheel so the engine spun down before the
>starter did.
>
>The solution? Move the start lead for the shower-of-sparks system from
>the starter side of the solenoid to the start button itself. Now the
>power went away instantly when the start button was released and the
>engine would catch and run just fine.
>
>BTW, this problem drove me nuts for about 6 months until I finally
>figured it out.
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