Doug,
What you are doing with the voltmeter is reading the voltage difference
between two points. In other words how much voltage is used up to
overcome the resistance in the circuit. Kind of like reading the water
pressure at each end of a garden hose. If you hook the voltmeter to the
battery, (positive lead to positive post and negative lead to negative
post), it will read battery voltage, roughly 12.6 volts with no load,
could be higher if the engine was just shut down because the charging
system is set to produce 13.5 to over 14 volts. With the voltmeter still
connected to the battery the reading while cranking will be
approximately 10 to 10.5 volts on a good system. That is how much
voltage the battery can produce with the starter operating. The reading
is also the voltage drop through the entire circuit.
By moving the negative lead back toward the positive side of the
circuit, from battery negative to the engine block, to the starter, to
the positive connection on the starter, to the battery post on the
solenoid, etc. a step at a time. With each move, part of the circuit is
eliminated from the voltmeter's reading and the voltage reading will be
reduced with each step back toward the positive post. Of course, the
biggest change will come when the lead moves to the positive side of the
starter, because the starter motor is eliminated from the reading.
I don't know how much you understand about electrical circuits, so I
have used lots of words to explain. The basic message is, to measure
voltage of a circuit the meter is connected in parallel, positive to
positive and negative to negative. An ammeter is hook up in series,
inside the circuit, all current used is passed through the meter (unless
an amp clamp is used, which measures amperage by sensing the magnetic
field created around the circuit as current passes through). Volt drop
is measured by connecting to the source and moving the other lead down
the same side of the circuit, further and further from the source.
If I could draw pictures with this thang it would be lots simpler to
explain. You really can't hurt the voltmeter though unless you try to
run current through it.
Tom, Redding CA - #216 D/CC
Doug Anderson wrote:
>
> oNE MANS FIFTEEN MIN'ITS IS ANOTHER MANS WEEKANAHALF....
> .KINDA LIKE OL' DIRTY DOUGS STARTIN' PRA'LEMS OF LATE.
>
> I'D LIKE'TA TAKE THIS OPER "TUNE" -ITY TO THANK YOU ALL FOR YOUR
> MOST EXCELLENT AND INFORMATIVE RESPONSES! I THINK WE'RE "OUT OF THE
> WOODS" NOW 'CAUSE WHEN I WENT HOME AFTER COLLEGGGG ALL DAY THE NEW BATTERY
> HAD BEEN ON TRICKLE FOR ABOUT 8 HOURS. TRIED IT, AND WHOOOM-BAH SHE'S
> MO-BETTA! A CLASSIC CASE OF "OLD AGE" BEFUDDLEMENT, ELECTRONIC WIZARDRY,
> AND TOO COOL "PRESUME ITS ALL SHOT 'CAUSE WE KNOW HOW TA FIX IT" HOT
> ROODERITIS ALL MIXED TOGETHER.
> IN OTHER WORDS,....I WORRY TOO MUCH.
>
> SOME OF YOUR ANSWERS WERE MOST INFORMATIVE AND THOUGHT PROVOKING AS
> WELL.
>
> IN ANSWER TO SOME OF YOUR QUERYS, MY POSITIVE BATTERY CABLE IS A FAT
> WELDING CABLE (FORGOT WHAT SIZE BUT ITS BIG...) MY 10" GROUND CABLE GOES
> FROM THE POST ON THE REARMOUNTED BATTERY TO THE FRAME. AT THE FRONT,
> ANOTHER LARGE CABLE GOES FROM THE L.S. ENGINE MOUNT BOLT TO THE BOLT HOLDING
> THE STEERING BOX TO THE FRAME RAIL. I KNOW ABOUT, AND AM CAREFUL TO MAKE
> ALL CONTACTS-INCLUDING THE ONE AT THE STARTER CLEAN AS A WISTLE.
>
> TOM, YOUR ADVISE ABOUT USING A VOLTMETER IS INTERESTING -I'VE NEVER HEARD
> OF IT BEFORE.....I'M A LITTLE UNCLEAR ABOUT PART OF WHAT YOU A SAID: " A
> volt meter can be put to use measuring volt drops through the circuit to
> locate the problems. Put the meter on low scale (2V) hook the positive lead
> of the meter on the battery post and the negative lead at the starter motor
> positive connection and take a reading with the engine cranking, ign off.
> Should be less than 0.5 volts. If you have a higher reading start moving
> the negative lead back toward the battery positive at each connection to
> locate the high resistance."
>
> JUST TO CLARIFY,....DO YOU MEAN TOM, THAT TO CHECK THE CRANKING, YOU
> HOOK UP BOTH POSITIVE AND NEGATIVE LEADS -FROM THE TESTER- TO THE BATTERY
> + POST AND TO THE LARGE HOT POST ON THE STARTER SOLONOID ?
> -A GUY SURE WOULD'NT WANT TO SCREW THAT UP…..
>
> MIGHT COULD BURN DOWN THE BARN THERE MYRTLE -COULD'NT YA?
>
> YOUR REPLY TO THIS QUERY COULD HELP US ALL IN A PINCH,….YES?
> THANKS AN EXTRA BUNCH TOM……
>
> SPECIAL THANKS TO YOU ALL:
>
> TOM BRYANT somewhere in sunny Cali... Redding is it?
> ARDUN DOUG in Nor Cal
> CHRIS HARRIS way, way, around th' otherside of da' worl'
> DICK J in East Texas -whom I'm now squatting on,but he's a good guy.
> BRYAN SAVAGE _don"t have a clue where you are>>>
> RACE 427 -Somewhereselse, New Yawk
> CHUCK ROTHFUSS Polecat Holler Nawth Ca'linnna
> KVACH BUTTERS - in AWESOME, IDAHO ?
>
> BOYS, I THINK WE GONNA BE ALLRITE AGIN NOW
>
> "DIRTY DOUG, and BOOGIE WOOGIE
> -in exile, in New Yawk -out by th' cows
>
> From: Dick J <lsr_man@yahoo.com>
> Reply-To: Dick J <lsr_man@yahoo.com>
> To: Finishline Coatings <lona@finishlinecoatings.com>,
> "land-speed@autox.team.net" <land-speed@autox.team.net>
> Subject: Re: Murphy's law
> Date: Thu, 27 Jul 2000 06:11:06 -0700 (PDT)
>
> Think of all the hours upon hours of fun we'd
> miss if those fifteem minute jobs actually took
> fifteen minutes. After all, we do this for fun,
> so the longer those fifteen minute jobs take, the
> more fun we have. NO?
>
> Dick J
>
> --- Finishline Coatings
> <lona@finishlinecoatings.com> wrote:
> > O.K. List..here's the way it is!!
> > The following words do not refer to anyone
> > living or dead, or are they
> > in any way intended to offend anyone - either
> > living or dead.
> > So here goes..I think that there is a
> > conspiracy going on..probably the
> > flat motor guys putting hexes on us inliners or
> > some one let "murphy"
> > loose in our shop the last couple of weeks!he
> > he heee.
> > About three weeks ago, we had a extra 400 turbo
> > rebuilt sitting on the
> > shelf so that we could change it in the ton
> > before B=ville. We did 22
> > shows and swap meets throughout the NW this
> > last winter and spring with
> > about 200,000 miles on the trans and I knew it
> > wouldn't pull the trailer
> > over the mountains. So, Saturday looked like a
> > good day. We borrowed a
> > trans jack, put the truck up in the air,
> > cardboard on the drive way and
> > went to work. Thought it would be about a
> > 4-hour job start to finish.
> > Wrong!!! Got the old one out in an hour..looked
> > everything over and the
> > out-put shafts are different. (I don't do
> > automatics-my mom told me
> > that the directions that came with me 60 years
> > ago said that I was given
> > a left leg to work a clutch pedal and a right
> > arm to shift a 4-speed.)
> > So, off to the trans man with the 2 autos. Six
> > hours later it's back in
> > the driveway ready to put in. The 4-hour job
> > has already taken 7. So
> > get it all in and mostly hooked up..(also
> > wanted to put on a cooler and
> > a new huge radiator I had built for going
> > through the mountains). The
> > original was in the same condition as the
> > trans. Sunday I figured about
> > 2-hours to finish it. Wrong!! The hoses were
> > to short, drilled a hole
> > in the overflow tank while drilling through the
> > radiator bulk head to
> > run the cooler lines through. I was the only
> > one working Sunday so I
> > had a nice walk to the auto parts store to get
> > what I needed. About the
> > only thing that went right was the push bar
> > mounts that I wanted to put
> > on while the truck was up in the air. Anyway
> > Monday comes and
> > everything looks good for getting the short
> > block back this week.
> > Wrong!! Marlo calls me early Monday morning to
> > tell me they gave me the
> > wrong rings (I'd even been talking nice about
> > the motor the last month
> > so that it would go together right.) (I didn't
> > call it a garbage truck
> > motor once!)
> > So went out to Marlo's shop and picked up the
> > rings (can't blame this
> > onto the flat motor guys), Bruce ordered them
> > for me and he's an
> > inliner! I think Murphys sitting on my shoulder
> > - they have to make the
> > rings special cause these pistons have been in
> > the motor since 1951. We
> > were looking at this weekend to put the car on
> > the chassis dyno. Wrong!!
> > Maybe next week. Anyway, the reason Marlos
> > putting the motor together
> > is because I don't have time with trying to get
> > the truck and trailer
> > together and change all the pedals and shifter
> > and steering wheel in the
> > roadster to fit Jacquie. There just isn't time
> > left to put this motor
> > together. After 3 years, I finally get to take
> > the car to Bville with
> > my own truck & trailer. They're not done by a
> > long ways but at least I
> > can use them. Anyway, back to the pistons and
> > special made rings...the
> > pistons are Veniolla made in '51. Down through
> > the years, I had to
> > replace 2 pistons. Back then ring sizes were
> > different than today. So
> > unless I re-machine the ring lands, I'm stuck
> > with having rings made.
> > Anyway, I'm letting Marlo handle this..he is a
> > Great Friend.
> > I went to use the small lathe to machine some
> > parts for the steering
> > extension and the carriage wouldn't move.So,
> > take it all apart and fix
> > it. The thing is - it's worn out. The lathe
> > was made in 1917 and is a
> > real piece of junk but it still makes parts for
> > me. So, 4-hours later,
> > it's working again and I can maybe get
> > something done. Looks like it
> > will be right down to the wire again this
> > year... like last. At least no
> > more pop rivets and racer tape holding the body
> > together while going to
> > the starting line.
> > Doug...I'll give you some more history on this
> > antique motor when we get
> > to B-ville. In spite of all the problems, its
> > still fun and I don't
> > complain cause I love to do it!!
> > Russ #902 XO
> > PS..Doug - they told me they shipped my new
> > roller this morning to late
> > for Speed Week this year. As I don't have any
> > lifters yet. So will run
> > with the McGurk I put in it in 1964. Not the
> > lift and center line I
> > want, but it's what I got. Lona can't
> > understand how I can stay so calm
> > with all these things happening. Hey, its part
> > of life. I told murphy to
> > buss off and you flat motor guys have your
> > problems too. At lease it's
> > not a dull life.
> > RM
> > PPS Ed..what gears are you wainting for? I
> > didn't know murphy had that
> > many cousins.
>
> =====
> .............................
> ..........Dick J.............
> ......(In East Texas)........
> ..........# 729..............
> ........Roadsters............
> .Hemis and Flatheads Forever.
> .............................
>
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