Received: with LISTAR (v1.0.0; list 61-79-list); Thu, 01 Feb 2001 18:42:35 -0500 (EST)
Date: Thu, 01 Feb 2001 18:42:35 -0500 (EST)
From: Ford Truck Enthusiasts List Server <listar ford-trucks.com>
To: 61-79-list digest users <listar ford-trucks.com>
Reply-to: 61-79-list ford-trucks.com
Subject: 61-79-list Digest V2001 #32
Precedence: list

==========================================================
Ford Truck Enthusiasts 1961-1979 Truck  Mailing  List

Visit our  web site: http://www.ford-trucks.com

To unsubscribe, send email to: listar ford-trucks.com with
the words "unsubscribe 61-79-list" in the subject  of  the
message.
==========================================================

Serious help restoring and maintaining your Ford truck!
----------------------------------------------------------
Check out the following items in our online store:
1961-1979 Factory Service (Shop) Manuals on CD-ROM
1961-1967 Factory Service (Shop) Manuals (Printed)
1963-1967 Wiring Diagrams
1957-1972 Ford Truck Illustrated Facts and Features manuals
1963-1967 Ford factory Engine Assembly Manuals
1961-1970 Ford Truck Body, Trim and Interior Assembly/Disassembly manuals

<a href="http://www.motorhaven.com/">
http://www.motorhaven.com/</a>

----------------------------------------------------------

------------------------------------
61-79-list Digest Thu, 01 Feb 2001 Volume: 2001  Issue: 032

In This Issue:
Engine won't stop (again)
Re: 460 lost oil pressure
Re: Flux capacitores and coils....
Re: Engine won't stop (again)
Re: 460 lost oil pressure
Re: Flux capacitores and coils....
Coil grounding
Vacuum dia
Re: 460 lost oil pressure
Lost oil pressure
oil pressure and amounts for 460?
Re: Engine won't stop (again)
Re: ENGINE WONT START
Thanks All For the Help
Re: Coil grounding
Engine won't start-update
Re: Engine won't stop (again)
Re: zip ties and hay bales, was:ENGINE WONT START
Re: Coil grounding
Re: Engine won't start-update
Re: zip ties and hay bales, was:ENGINE WONT START
Re: Engine won't stop (again)

----------------------------------------------------------------------

Date: Thu, 01 Feb 2001 08:49:14 -0600
From: John Strauss <jstrauss inetport.com>
Subject: Engine won't stop (again)


>OK OK, ya got me.  The flux is built when the points are open, voltage from
>the primary side of the coil < read a small number of copper wire windings
>wraped around a iron core> is inducing a current into the secondary windings
><read MANY more windings of copper wire wrapped around an iron core> . This
>creats a very high voltage, around 25 thousand volts, with VERY low current.
>Thats why people can get a very uncomfortable feeling touching a plug wire
>yet live to tell about it. :)  The flux builds up within the coil when the
>points are open, the flux field collapses when the points close and put a
>ground on the - side of the coil.  This 25 KV flux field is disharged to the
>secondary side of the coil. < the coil wire> The coil wire output is ALWAYS
>referred to as the secondary output.  The + and - side of the coil are
>ALWAYS referred to as the primary voltage circuit.  What I was trying to say
>last night was, if you held the + or - negative side of the coil to ground,
>you will not have this building and disharge of voltage which is commonly
>referred to as the flux field.  Bottom line, you ground any of the three
>connections from your coil,<err, and hold it there> your truck will not have
>fire to the plugs!
>
Wait, wait, wait, hold the phone.  The coil energizes when the points are
CLOSED and the field collapses when the points OPEN, which fires the coil.
Right?  That's why a smaller gap gives the coil more time to saturate
because the points are closed longer, right?  Or have I been deceived all
my life?
  _
_| ~~.  John Strauss
\, *_}  jstrauss inetport.com
  \(    Texas Fight!


------------------------------

From: "Jeff Bennett" <jmb40 amexol.net>
Subject: Re: 460 lost oil pressure
Date: Thu, 1 Feb 2001 10:01:55 -0500


I had a problem with my 460, where the oil pressure would fall low
at idle. It got progressively worse until it finally lost oil pressure.
I found the bolts holding the pump to the block had worked loose. One
had fallen completely out, and the other was worked half way out. I guess
who ever was in the bottom end last didn't tighten them up. I reattached
the pump and had no more problems. I just have pulled the engine out of
the parts truck it was in, to begin a rebuild on it, in preparation to
put it in my 70 camper special, and when I pulled the pan off the pump
was still tight.

jb

-----Original Message-----
From: 61-79-list-bounce ford-trucks.com
[mailto:61-79-list-bounce ford-trucks.com]On Behalf Of Karl Streich
Sent: Thursday, February 01, 2001 1:33 AM
To: 61-79-list ford-trucks.com
Subject: [61-79-list] 460 lost oil pressure


----------------------------------------------------------
Support FTE - Check out our store:
http://www.motorhaven.com/
----------------------------------------------------------

HI

My '77 460 lost oil pressure the other day, it started at about half of
normal oil pressure, 1/4 of the way up the scale, and over 10 minutes droped
to nothing, asside from the obvious insturment malfunction what might be the
culprit???

Karl
_________________________________________________________________
Get your FREE download of MSN Explorer at http://www.ford-trucks.com//lc/lc.php?action=do&link=http://explorer.msn.com

=============================================================
To  unsubscribe:   www.ford-trucks.com/mailinglist.html#item3
Please remove this footer when replying.



------------------------------

From: "GaryBBB" <gpeters3 lni.net>
Subject: Re: Flux capacitores and coils....
Date: Thu, 1 Feb 2001 09:05:02 -0800


I'm not an engineer but I know one thing about spark...the flux is built up
or the primary coil is "Saturated" while power is applied to it.  The energy
is actually stored in the primary coil wires in the form of magnetic flux
which radiates outward and passes through and beyond the secondary coil
wires.  While power is applied it also induces voltage into the secondary
which at that point has no way to flow (I presume from what you all are
saying?) At this point the secondary coil has very little energy because
once the primary is fully saturated the flow is reduced significantly so it
just sits there twiddling it's thumbs.  All of the energy is actually stored
in the primary (by way of the magnetic flux) until the input side of the
coil is shorted to ground or the circuit is opened (which ever they are
doing?)  Since the applied power is DC there is no significant inductance to
the secondary coil until the power is cut off suddenly and the magnetic
field collapses which it does very quickly because the iron core is pure
iron, deliberately softened so that it won't retain any magnatism.  It has
to be done in this way becasuse the saturation process (which does induce
some voltage into the secondary) takes too long and the energy developed is
insufficient to make the spark.

Now, HOW they make that happen is a little fuzzy to me right now but at some
point the secondary coil HAS to have a ground for current to flow.  I
suspect that the secondary is grounded at the same time the flux capacitor
(kidding:-)) is drained when the points close which is done electronically
with transistors in the dura spark system.

If the green wire is broken you will not get spark because no ground can be
made.  It is possible that there is no ground connection to the coil can as
everyone is saying but the loose coil failure is still a mystery to me and I
will test the theory one day soon and report on my findings :-)

BTW, there is considerable current while the field is collapsing but it is
of very short duration so has no serious effect on humans, much like passing
your finger through a match flame quickly.....there isn't time for your skin
to absorb much energy so it "Seems" like there isn't much there.  Remember
that it is current that produces heat, not voltage.....the voltage produces
the force to cause current to flow when the points are opened etc. but it
only flows for a millisecond.  We don't feel the heat but gasoline does :-)
(fortunately for most of us :-))

The reason we are not shocked by a 12v battery is that there isn't enough
"Voltage" to "force" enough courrent through our very high resistance skin
to produce sufficient current to bother us.  As you increase the voltage
this natural resistance is overcome and you feel the "shock".  If you are
wet and well grounded then you feel a shock at lower voltages and if there
is any inductance in any part of the low voltage apparatus you are messing
with you can get a serious shock because this can increase the "Voltage"
enough to shock you just as a coil does.

When welding you have only about 25-40v in the rod (typically) but because
your work is well grounded and you have oil and moisture in your skin you
can, on damp days especially, get a little shock when replacing the rods if
you are leaning against the work.  There is also some inductance and
capacitance going on there so when the rod is not actually working the
voltage can build up etc.....Ain't electricity fun?  Here's another place we
can argue some :-)  The heat here is produced by the air gap just like in a
spark plug.....why does a spark plug with roughly the same gap require so
much more "Voltage"???  I'm actually serious here??

--
Happily Retired (but broke)
Michigan Pot Hole Jumping,
78 Bronco Loving, Gary
--

> OK, this is fun.  I know what your saying and I agree 100% with you.  Just
> want to point out that what we write isn't exactly what we were thinking.
> Sometimes it's hard to convey a piont.  Lord knows I do it all
> the time and
> will probably do it here again. :)


------------------------------

From: "GaryBBB" <gpeters3 lni.net>
Subject: Re: Engine won't stop (again)
Date: Thu, 1 Feb 2001 09:12:25 -0800


No, that's how I remember it too.  Closing the points energizes the
primary....opening them collapses the flux producing inductance in the
secondary coil.  The capacitor is there to absorb "Battery" voltage while
the points are open so they don't arc and has nothing to do with the coil
operation other than to ensure that the points do what they are supposed to
do, Make and break the voltage to the primary QUICKLY :-)  What you are
talking about is "Duration".  More duration (points open longer via opening
to greater gap in most cases) means longer spark life but also less time for
primary saturation.  This is why they have gone to "Coil on plug"
technology.  It allows full saturation of the primary side of the coil for
much hotter spark at higher rpms.

I may not know how the coil is grounded but I do know a few things :-)

--
Happily Retired (but broke)
Michigan Pot Hole Jumping,
78 Bronco Loving, Gary
--

> Wait, wait, wait, hold the phone.  The coil energizes when the points are
> CLOSED and the field collapses when the points OPEN, which fires the coil.
> Right?  That's why a smaller gap gives the coil more time to saturate
> because the points are closed longer, right?  Or have I been deceived all
> my life?


------------------------------

From: daves8 juno.com
Date: Thu, 1 Feb 2001 08:25:58 -0700
Subject: Re: 460 lost oil pressure


Check it the easy way.

Install a mechanical oil pressure gauge at the block and see what the
pressure actually is.  Best way to cut through all the uncertainty and
find out if you actually have a problem.


Dave Schoenberg
Arvada, Colorado

On Wed, 31 Jan 2001 22:32:36 -0800 "Karl Streich" <fordlist hotmail.com>
writes:
> My '77 460 lost oil pressure the other day.........
________________________________________________________________
GET INTERNET ACCESS FROM JUNO!
Juno offers FREE or PREMIUM Internet access for less!
Join Juno today!  For your FREE software, visit:
http://www.ford-trucks.com//lc/lc.php?action=do&link=http://dl.www.juno.com/get/tagj.

------------------------------

From: "GaryBBB" <gpeters3 lni.net>
Subject: Re: Flux capacitores and coils....
Date: Thu, 1 Feb 2001 09:58:26 -0800


Oooooops, point are opened, not closed, sorry :-)  Thank's John for
reminding me.  The points close to energize the flux and open to collapse it
and that's final :-)  I'm reasonably sure it is done the same way
electronically as well because collapsing the magnetic field is a much
faster process and produces the greatest amount of inductance in the
secondary so it has to be done this way.

Turn on the power to saturate the coil and build the flux and turn off the
power to "Induce" the current for spark.

--
Happily Retired (but broke)
Michigan Pot Hole Jumping,
78 Bronco Loving, Gary
--

> Now, HOW they make that happen is a little fuzzy to me right now
> but at some
> point the secondary coil HAS to have a ground for current to flow.  I
> suspect that the secondary is grounded at the same time the flux capacitor
> (kidding:-)) is drained when the points close which is done electronically
> with transistors in the dura spark system.


------------------------------

From: "Azie L. Magnusson" <maggie11 HiWAAY.net>
Subject: Coil grounding
Date: Thu, 1 Feb 2001 09:54:29 -0600

Dennis P writes:  >>Is it possible there is a difference in the newer (electronic) systems
and the old (standard ignition) style like I have?  That could be the
source of some of the disagreement.   I thought I understood how to hook
up a coil for the last 40 years or so, but now I'm really confused...All
these years I believed if the secondary side of the coil, the side that
goes to the condenser/points, got grounded, that the points wouldn't
fire...Now...?  If the can is grounded and the secondary contact is
connected to the can, then that provides a reason for the points to fire
(seeking a ground ?)...I better get back to research papers.  And I
think I'll just replace the coil in that Cleveland and tear the old one
apart...<<

I may be all wet, but this is the way I've always thought it to be:  The
primary side and the secondary side share a common ground(which is
the points) and the switched battery voltage is supplied to the positive
terminal and the high voltage is exited by the coil wire..  When the
points close, the voltage flows through the primary side then ceases as
the points open back up, causing the magnetic field to expand and
collapse causing voltage in the secondary..  Neither side need be
grounded until a spark is needed!!!  Am I close??? Don't have a clue
how that reluctor in the electronic units works, but the results are great.

Azie Magnusson
Ardmore, Al.


------------------------------

From: "Azie L. Magnusson" <maggie11 HiWAAY.net>
Subject: Vacuum dia
Date: Thu, 1 Feb 2001 09:57:22 -0600

John LaG, writes:  >>For sure there is a difference in the years.
Tonnage makes a difference, too.<<

That makes sense to me.


Azie Magnusson
Ardmore, Al.


------------------------------

From: "GaryBBB" <gpeters3 lni.net>
Subject: Re: 460 lost oil pressure
Date: Thu, 1 Feb 2001 10:05:40 -0800


With the 460 it is less frequent than the 335 series engines but it is still
possible to twist off the dizzy/oil pump drive shaft and dizzy roll pin in
the gear due to a seized pump but in that case you would not get any
pressure ever and the engine will eventually, if not immediately, die and
fail to restart.

If this happened suddenly then a wire to the sender or the sender itself
could be the problem.  If it happened over time and now has zero at idle
when warm then it's bearings or clogged screen or pump is falling off as
mentioned.

If you don't have any gauges to stick on it just loosen a gallery plug or
the oil sender itself, which ever is easiest to get at and start the engine
and pull it out, slowly to see if any oil squirts out the threads.  If you
don't mind the mess you could just pull it out and be ready to shut off the
engine:-)  If oil squirts out you do have pressure :-) (wear safety glasses
for this though)

--
Happily Retired (but broke)
Michigan Pot Hole Jumping,
78 Bronco Loving, Gary
--

> HI
>
> My '77 460 lost oil pressure the other day, it started at about half of
> normal oil pressure, 1/4 of the way up the scale, and over 10
> minutes droped
> to nothing, asside from the obvious insturment malfunction what
> might be the
> culprit???
>
> Karl


------------------------------

From: "Azie L. Magnusson" <maggie11 HiWAAY.net>
Subject: Lost oil pressure
Date: Thu, 1 Feb 2001 10:14:57 -0600

Karl S. wriotess:  >>My '77 460 lost oil pressure the other day, it started at about half of
normal oil pressure, 1/4 of the way up the scale, and over 10 minutes droped
to nothing, asside from the obvious insturment malfunction what might be the
culprit???<<

Could be many things, but I'd be sure I had oil pressure before I drove
it again..  Most likely if the lifters are not clattering very loudly, then you
really do still have oil pressure, but I'd want to know for sure.  Those
460's do not overhaul cheaply.  I'm in the middle of a complete rebuild
of a '77 460 right now..  Those parts places really love their 460 parts..
A mechanical gauge could let you know for sure.
As suggested by this list on many previous occasions to test the gauge,
simply take the wire off the sending unit and ground it.  Your gauge
should deflect to maximum oil pressure(with ignition on of course).
If it doesn't then the wire or the gauge or the IVR(Instrument voltage
regulator) may be bad.  The IVR controls the temp gauge also, so if
it is OK, then it will be either the wire or the gauge.  If it does reflect
to maximum pressure when you ground the wire, then it is most
likely the sending unit.  Most auto parts stores carry these, and they
are easily replaced.  Yours in on the very top/rear of the engine -
single wire going to it.


Azie Magnusson
Ardmore, Al.


------------------------------

From: "Bob" <xavetarx home.com>
Subject: oil pressure and amounts for 460?
Date: Thu, 1 Feb 2001 12:39:48 -0500


While on the subject of oil...

Is it normal for the gauge to read real high at start, and then slowly come
down to 35-50 and then stay?

Also, what should the amount of oil be (quarts)?  I changed the oil with the
idea that it should have 7 quarts.  However, while adding, I checked at 6,
and it read too much.  I've never heard of a 6 (or less??) quart oil pan on
a 460, but I may be wrong.  The plug is on the front side of the engine, not
the back (make a difference?).  I'm not sure what 460 it is, as when I
bought the truck (79 bronco) it already had been swapped in.  I do notice a
slight chatter of the lifters.  Any ideas, or experience with such a reading
being false?.. Should I just put in 7?

Thanks,

-bob-
79 Bronco 460 44's T18
79 Bronco 400 40's C6



------------------------------

From: luminous neteze.com
Date: Thu, 01 Feb 2001 09:44:22 -0800
Subject: Re: Engine won't stop (again)


Gary wrote:
>No, that's how I remember it too.  Closing the points energizes the
>primary....opening them collapses the flux producing inductance in the
>secondary coil.  The capacitor is there to absorb "Battery" voltage while
>the points are open so they don't arc <<

Gary, this is correct up to this point. When the points close, current
flows thru the primary winding, building up a magnetic flux.
When the points open, primary current continues to flow for a very
brief time until the condensor is fully charged to battery voltage.
The condensor helps protect the points by acting as a "shock absorber"
to keep current from arcing across the points as they begin to open.
Once the condensor is "full", no more current flows and the magnetic
field collapses. As the field collapses it induces a voltage in the
secondary winding.

>and has nothing to do with the coil
>operation other than to ensure that the points do what they are supposed to
>do, Make and break the voltage to the primary QUICKLY :-)

Here is where we disagree.  The condensor has a second function.
When the points open, the magnetic field collapses and induces
a voltage in the secondary winding. One end of this winding is
essentially attached to a spark plug, and the other end is
attached to the points, along with one end of the primary winding.
If the condensor did not exist, the energy from the secondary
would not only jump the spark plug gap, it would also jump
across the points gap to find ground. Obviously this would be
bad, since the spark has to waste energy jumping a second gap
and would also damage the points in a big hurry.
The condensor provides the ground path for the secondary current.
This current appears as a very brief pulse, which the capacitor
can pass to ground with very little resistance.
Remember that a capacitor will block current flow in a DC circuit
(once the capacitor is fully charged), but will pass an AC current
or brief DC pulse quite readily, according to the formula for
capacitive reactance.             1
                          Xc= ---------
                                2PiFC

Where Xc is the capacitive reactance in ohms
      F is the frequency in cycles per second
      C is the capacitance in Farads
      Pi is ~3.1416

It is this capacitor which effectively "grounds" the secondary
winding when the points are open.
There is no other ground for the secondary. It is in no way
tied to the can of the coil.

Simple electronic ignitions, such as Duraspark operate identically,
except that the points are replaced with a transistor.

Gary, here's a simple experiment for you to try.
Take your ohmmeter, set on the highest ohms range and measure
the resistance from each of the 3 coil terminals to the case.
In each instance it will (should) read infinite ohms.
This verifies that there is no connection from any winding
to the case.
Now measure from the secondary terminal to the "-" terminal.
Resistance will likely be somewhere from 5K-15K ohms. This
is the resistance of the secondary coil, and verifies that one
end of this coil is internally connected to the "-" terminal.
Now measure the resistance from the "+" terminal to the "-"
terminal. This is the primary winding and will likely measure
around 1-2 ohms. Measuring from the "+" terminal to the secondary
(H.V.) terminal would produce a reading thats the sum of the 2
winding resistances.

Let us know if you find any coils where the secondary is connected
to the case and not the "-" primary terminal. I'd like to know
where it came from, since I've never seen such a beast.
(but there's always a first time!)

Cheers,

  Jim Imboden
  1970 F100, 240/6  T-18

 luminous neteze.com




------------------------------

From: luminous neteze.com
Date: Thu, 01 Feb 2001 09:44:24 -0800
Subject: Re: ENGINE WONT START


John wrote:
>Thanks, Jim. My Ford experience is rather limited. I know my uncle used to
>tell me that if the coil ever shorted to ground, you could unbolt it, lay it
>up on the engine wrapped in a rag and get home. In those days I was driving
>stuff from the general.

John,
Yeah, that makes sense.  The likely internal coil failures are:

1) Burned out (open) winding.
2) Inter-winding short.
     (insulation breakdown and adjacent coils short together)
3) Winding to can short.
     (insulation breakdown and coils short to iron core and/or can.)

 In the case of 1) or 2) it's time to start walking, but in 3),
unbolting the coil and insulating the case from ground just might
get you home. (-:

>Zip ties hadn't been invented.

 Come on John, that's rediculous. I think Zip ties have *always*
been around. (-:
How could primitive man ever have evolved into decent mechanics
without zip ties? I'm sure they must have been one of the first
tools ever invented, but they were probably made of stone or bronze
or something. Personally, I can't even imagine life without them!

Cheers,

  Jim Imboden
  1970 F100, 240/6  T-18

 luminous neteze.com




------------------------------

From: "mail.in-tch.com" <tet2met in-tch.com>
Subject: Thanks All For the Help
Date: Thu, 1 Feb 2001 12:01:28 -0800

I would like to thank everybody for the response to my vacuum question. Soon as the weather breaks here, I will see what I can get done. To respond to some comments, I have a neighbor who has a 78 with a 400hp with a standard transmission and it wasn't even close to what I have. I have also been looking for the decal that shows the schematic for the vacuum with out success. Thanks again for all the suggestions.

Tom


------------------------------

From: daves8 juno.com
Date: Thu, 1 Feb 2001 12:18:00 -0700
Subject: Re: Coil grounding



Like some guys already have said.....

The points close and energize the primary side of the coil.  When the
points open, the field collapses into the iron core.  Faraday's Law says
that you generate electricity with a magnetic field, a conductor and
relative motion between the two.  The collapsing field actually creates
the relative motion with the conductor ( the iron core inside the coil
that goes to the high-tension lead) and therefore the voltage is
generated.  This voltage (30,000 volts or so) jumps the gap across the
plug electrodes and creates the spark.

The secondary side is basically static electricity -- no ground is there
and no ground is needed.  Just like lightning.

Dave Schoenberg
Arvada, Colorado
________________________________________________________________
GET INTERNET ACCESS FROM JUNO!
Juno offers FREE or PREMIUM Internet access for less!
Join Juno today!  For your FREE software, visit:
http://www.ford-trucks.com//lc/lc.php?action=do&link=http://dl.www.juno.com/get/tagj.

------------------------------

From: "Gary Tobolski" <garyt mediaone.net>
Subject: Engine won't start-update
Date: Thu, 1 Feb 2001 15:15:07 -0500


Hello.  First of all, thank you everyone that offered advice.

The first problem was that the engine stopped cranking.  I knew the battery
was good, but had the battery and starter tested anyway.  Both were good, so
I replaced the solenoid.  Problem solved.

Next was the engine kicking back after releasing the starter.  Everyone
recommended timing, but I didn't think so since the distributor hadn't been
out.  The problem was that I connected a vacuum advance line, and this
wasn't connected last time.  Remove the line, and the problem is solved.

The last problem turned out to be getting the fuel to the engine.  It turns
out that I've got a bad fuel pump.  Brand new out of the box, so I didn't
think this was my problem.

Now for my question.  The fuel pump that was on the engine has three
connection points, which I was told was to return the fuel to the tank.  I
know this pump is good, so I would like to know which connection is the
return line.  Also, can I either just plug the line, or put a t-fitting just
before the fuel pump to connect this to?  Or am I just going to have to run
a return line to the tank to use this?  Thanks again for all the help.
Eric Tobolski


------------------------------

From: "John LaGrone" <jlagrone ford-trucks.com>
Subject: Re: Engine won't stop (again)
Date: Thu, 1 Feb 2001 14:36:51 -0600


>snip<
>  If the condensor did not exist, the energy from the secondary
>  would not only jump the spark plug gap, it would also jump
>  across the points gap to find ground. Obviously this would be
>  bad, since the spark has to waste energy jumping a second gap
>  and would also damage the points in a big hurry.

OK, the primary circuit goes to the battery and the secondary fires the
plugs, right? The primary goes through the points, not the secondary. Hot
wire from the B+ goes to + side of the coil. - side of the coil goes to the
points. Primary grounds when points are closed. All that little bitty
condensor does is prevent radio noise. My 79 runs well whether I have that
condensor or not. I know..the 79 is Duraspark.

>  The condensor provides the ground path for the secondary current.

The secondary circuit goes from the high tension output to the center of the
distributor cap, through the rotor, to the spark plug, to ground when it
sparks. Period. Look at a single cylinder magneto lawnmower or motorcyle
ignition. They don't even have a battery, but still need the points in the
primary side to fire the plug. Secondary goes straight from the coil to the
spark plug.

>which the capacitor can pas to ground with very little resistance.
>  Remember that a capacitor will block current flow in a DC circuit
>  (once the capacitor is fully charged), but will pass an AC current
>  or brief DC pulse quite readily, according to the formula for
>  capacitive reactance.             1
>                            Xc= ---------
>                                  2PiFC
>
>  Where Xc is the capacitive reactance in ohms
>        F is the frequency in cycles per second
>        C is the capacitance in Farads
>        Pi is ~3.1416

Looks good. I'll pass on this section.

>
>  It is this capacitor which effectively "grounds" the secondary
>  winding when the points are open.
>  There is no other ground for the secondary. It is in no way
>  tied to the can of the coil.

Nope, I don't buy this.

>
>  Simple electronic ignitions, such as Duraspark operate identically,
>  except that the points are replaced with a transistor.

Correct. Or an optical switch.

--John LaGrone
jlagrone ford-trucks.com
See Henry at: http://www.ford-trucks.com/jlagrone/henry.home.htm


------------------------------

From: "John LaGrone" <jlagrone ford-trucks.com>
Subject: Re: zip ties and hay bales, was:ENGINE WONT START
Date: Thu, 1 Feb 2001 14:43:21 -0600


>snip<
>   Come on John, that's rediculous. I think Zip ties have *always*
>  been around. (-:
>  How could primitive man ever have evolved into decent mechanics
>  without zip ties? I'm sure they must have been one of the first
>  tools ever invented, but they were probably made of stone or bronze
>  or something. Personally, I can't even imagine life without them!


Like Darrell said a couple of days ago: baling wire. You see all hay bales
were rectangular, not round, and tied with wire, not string. Believe it or
not a hay bale could be lifted by a single man and you could haul a goodly
number in the back of your F series truck. I know there are some people
still using the older bale style, but around here almost everyone uses the
giant round bales.

--John LaGrone
jlagrone ford-trucks.com
See Henry at: http://www.ford-trucks.com/jlagrone/henry.home.htm


------------------------------

From: "John LaGrone" <jlagrone ford-trucks.com>
Subject: Re: Coil grounding
Date: Thu, 1 Feb 2001 14:47:47 -0600


> The secondary side is basically static electricity -- no ground is there
> and no ground is needed.  Just like lightning.

In principal correct, technically incorrect. Electricity always needs a
ground to complete the circuit and move. Actually, the negative side of a
potential is where the electrons exist in surplus, so electricity really
moves from negative to positive. Until the mid 50s, most cars and trucks
were positive ground. The popularity of AM radio changed all of that.

--John LaGrone
jlagrone ford-trucks.com
See Henry at: http://www.ford-trucks.com/jlagrone/henry.home.htm


------------------------------

From: "John LaGrone" <jlagrone ford-trucks.com>
Subject: Re: Engine won't start-update
Date: Thu, 1 Feb 2001 14:58:31 -0600


> Next was the engine kicking back after releasing the starter.  Everyone
> recommended timing, but I didn't think so since the distributor hadn't
been
> out.  The problem was that I connected a vacuum advance line, and this
> wasn't connected last time.  Remove the line, and the problem is solved.

Not solved. Without vacuum advance, your engine will not perform properly
over the full operating range.

> Now for my question.  The fuel pump that was on the engine has three
> connection points, which I was told was to return the fuel to the tank.  I
> know this pump is good, so I would like to know which connection is the
> return line.  Also, can I either just plug the line, or put a t-fitting
just
> before the fuel pump to connect this to?  Or am I just going to have to
run
> a return line to the tank to use this?  Thanks again for all the help.

You should be able to plug the return port with a brass plug and use the
pump. If possible, I would return it to the seller and get the correct pump.

--John LaGrone
jlagrone ford-trucks.com
See Henry at: http://www.ford-trucks.com/jlagrone/henry.home.htm


------------------------------

From: "wish" <wish ford-trucks.net>
Date: Thu, 1 Feb 2001 22:11:24 GMT
Subject: Re: zip ties and hay bales, was:ENGINE WONT START


>baling wire. You see all hay bales
>were rectangular, not round, and tied with wire, not string. Believe it or

>not a hay bale could be lifted by a single man and you could haul a goodly

>number in the back of your F series truck. I know there are some people
>still using the older bale style, but around here almost everyone uses the

>giant round bales.
>


My grandfather still bales the small square ones, for some reason the "horsey"
people like them 'cause there's lest waste.  I was able to make a killing when
I was a student by working on the small farms around here that still do use
the small bales.  Its hard to find kids to do the work anymore and most of the
farmers are too old or have heart problems, so they pay well for a couple fields
worth of work :)

Oh yeah and part of my Christmas present before my 16th birthday was some bailing
wire.  The family joke is that you need bailing wire to hold old Ford truck's
together ever since Grandpa used it to hold the sides of his rattletrap together
after a particularly enthusiastic load of bales.  The irony was that my cousin
with his brand-x machines has used all of his wire up and gone to duct tape,
while I've still got all they gave me around here somewhere ...

Just my $.02
wish

96 Mustang GT 5spd 4.6L
73ish 1/2ton 4x4   6.4L
http://www.ford-trucks.com//lc/lc.php?action=do&link=http://www.public.iastate.edu/~wish

Ford Truck Enthusiasts
http://www.ford-trucks.com

------------------------------

From: luminous neteze.com
Date: Thu, 01 Feb 2001 14:41:07 -0800
Subject: Re: Engine won't stop (again)



>>snip<
>>  If the condensor did not exist, the energy from the secondary
>>  would not only jump the spark plug gap, it would also jump
>>  across the points gap to find ground. Obviously this would be
>>  bad, since the spark has to waste energy jumping a second gap
>>  and would also damage the points in a big hurry.

John replied:
>OK, the primary circuit goes to the battery and the secondary fires the
>plugs, right?

Right.

>The primary goes through the points, not the secondary.

Well, the "non spark-plug end" of the secondary coil is connected
to the "-" end of the primary winding which in turn is connected
to the points...
Primary current flows thru the points, but no secondary current
actually flows thru the points, since secondary current occurs
when the points are open. However, this secondary current flows
thru the condensor which is wired in parallel with the points.

>Hot
>wire from the B+ goes to + side of the coil. - side of the coil goes to the
>points. Primary grounds when points are closed.

Right.

>All that little bitty
>condensor does is prevent radio noise.

Are we talking about the same condensor? I'm speaking of the
one that is inside the distributor, wired in parallel with the
points. This is what AC couples the secondary winding to ground
when the points are open.

>My 79 runs well whether I have that
>condensor or not. I know..the 79 is Duraspark.

I'm thinking that you must be refering to the capacitor
which is sometimes connected from the * B+ * side of the coil
to ground. Yes, this does just reduce radio interferance.

>
>>  The condensor provides the ground path for the secondary current.
>
>The secondary circuit goes from the high tension output to the center of the
>distributor cap, through the rotor, to the spark plug, to ground when it
>sparks. Period.

Well, yeah that's where ONE end of the secondary winding goes.
But a coil of wire has 2 ends, right?
And current needs a conmplete circuit to flow, so the OTHER
end of the winding has to be connected *somewhere*.
The other end is connected to the "-" end of the primary winding,
which in turn is connected to the distributor points AND the
condensor which is wired in parallel with the points.
It is this condensor which provides the current pathway to
ground for the secondary winding when the points are open.
Here's a crummy ASCII veiw of the circuit:

B+ >----------+    S------> H.V. to rotor, cap, spark plug---Ground
              P    E
              R    C
              I    O
              M    N
              A    D
              R    A
              Y    R
              |    Y
         "-"  |----|
              |      < Primary winding, secondary winding,
              |        points, and condensor are all connected
              |----C   together to the "-" terminal of the coil
              P    O
              O    N
              I    D
              N    E
              T    N
              S    S
              |    O
              |    R
              |    |
              Ground

Battery voltage (B+) is applied to one end of the primary winding.
When the points are closed, current flows thru the primary winding,
thru the points, and to ground. The condensor does nothing since
it is directly shorted out by the points.
Current flow thru the primary winding builds up a magnetic field
within the coil.
When the points open, current stops flowing thru them. However
current thru the primary continues very briefly until the condensor,
which is wired across the (now open) points, is charged to battery
voltage. At this point, when the voltage on the capacitor is the
same as the battery voltage, no more current can flow. Current
thru the primary winding has ceased, and now the magnetic field
collapses. As the field collapses, it induces a voltage across
the secondary winding. The current path for the "business end"
of the secondary is already understood...
Like so:  Secondary winding-rotor-cap-sparkplug-ground.

But the other end of the winding needs an effective path to ground
to complete the circuit...
The points are open, so that's not it.
The condensor across the points serves this function.
Altho the condensor blocks the steady state DC voltage from the
battery, it will readily pass an AC current, or a brief DC pulse,
such as is generated by the secondary winding.
This condensor IS the current return path to ground for the
end of the secondary that doesn't go to the spark plugs.
If the condensor did not exist, the voltage would find it's
way to ground by jumping across the contact points.

>>  It is this capacitor which effectively "grounds" the secondary
>>  winding when the points are open.
>>  There is no other ground for the secondary. It is in no way
>>  tied to the can of the coil.
>
>Nope, I don't buy this.

Which part don't you buy? Do you believe the secondary is connected
to the can internally, and not to the "-" end of the primary?
If so, I believe you're wrong.

Do you believe the secondary is connected to the "-" end of
the primary and not the can (which is true), but not believe the
part about the condensor being the secondary return path to
ground?  If this is the case, how would you suggest the secondary ....


To access the rest of this feature you must be a logged in Registered User Of Ford Truck Enthusiasts

Registration is free, easy and gives you access to more features.
If you are not registered, click here to register.
If you are already registered, you can login here.

If you are already logged in and are seeing this message, your web browser is blocking session cookies. Change your browser cookie settings to allow session cookies.




Advertising - Terms of Use - Privacy Policy - Jobs

This forum is owned and operated by Internet Brands, Inc., a Delaware corporation. It is not authorized or endorsed by the Ford Motor Company and is not affiliated with the Ford Motor Company or its related companies in any way. Ford is a registered trademark of the Ford Motor Company.