97 plymouth slow crank No Start????

Discussion in 'General Motoring' started by punkoboy, Sep 13, 2006.

  1. punkoboy

    punkoboy Guest

    I have a 3.3 engine,took the top half off this spring to replace head
    gaskets, valve cover,seals etc. Put it all back together and it ran
    fine. I took it off the road to do this work so i haven’t driven it
    only started it from time to time. After a few times it started
    cranking real slow then it would start ok. Now its just slow. checked
    connections, took the starter out and had it checked, was alittle
    variable on the amps so i replaced it. still the same maybe alittle
    faster. checked fuel pressure was good. has 157,000 on it and have had
    it since new with no problems. I’m missing something here, any
    suggestions would be great. Thanks.
    punkoboy, Sep 13, 2006
  2. punkoboy

    maxpower Guest

    What does fuel pressure have to do with slow crank? And I see no mention of
    having the battery tested?

    Glenn Beasley
    Chrysler Tech
    maxpower, Sep 13, 2006
  3. yes- you are missing something- the battery is dead from sitting- and
    needs to be charged or replaced- also the alternator may be bad and not

    you need to do a charging test on the alt., and a battery load test
    after it is first charged
    duty-honor-country, Sep 13, 2006
  4. punkoboy

    punkoboy Guest

    Not so fast!!! I’ve been around the block a few times. It has a new
    battery out of my 64 pickup. Even if the alternator was bad it still
    would start. Good guess. I would not be here if it were that simple.
    punkoboy, Sep 14, 2006
  5. punkoboy

    DeserTBoB Guest

    Don't listen to "shirked duty-dishonor-country" aka Charlie Nudo. He's
    the resident troll.

    Nippondenso starters have a characteristic problem with solenoid
    contacts. If you're cranking slow and not drawing enough current to
    significantly dim the interior lights, look at the solenoid contacts.
    You could also check the tightness of the battery cable to the
    solenoid itself, but ND starters have been prone to this sort of
    failure since the '70s.
    DeserTBoB, Sep 14, 2006
  6. punkoboy

    JustSayGo Guest

    Use a DVOM, paper and pen.
    Connect the leads measuring volts at the battery posts, crank the
    engine and record your reading. You should read 10.5+ V

    Next connect one lead to the neg battery post and one to the block,
    crank the engine and record your reading. You should measure .1v. Just
    like golf, low scores are good.

    Next connect one lead to the pos battery post and the other to the
    starter motor post, crank your engine and record. You should measure
    3v. Again JLGLSAG

    If either voltage reading is greater, move the engine side probe closer
    to the battery and crank until you find your bad connection. You won't
    be missing anything.

    Even after you find the big problem continue testing. With the eng
    running, Neg bat post to alt case should be .1v. Pos Bat to alt charge
    post should be .2v

    Measure the voltage differential from the battery to the body and eng
    to body.
    JustSayGo, Sep 14, 2006
  7. No, if the alternator was bad, and you ran the engine for any amount of
    time, the draw from the ignition, and from repeated starts, would drain
    the battery in short time.

    Don't assume the battery is good just because it's "new" IYO, have a
    draw test done on it. I've seen many a 5-year warranty battery give up
    the ghost at 1 year and have to be returned and pro-rated, for a new

    You also have to do a current draw test on the starter.
    duty-honor-country, Sep 14, 2006
  8. punkoboy

    maxpower Guest

    When you have a slow crank problem and you mention checking fuel pressure
    some people may question how many times you have been around the block!! Not
    to degrade you in anyway but checking the battery question had to be asked
    after I read that!!

    maxpower, Sep 14, 2006
  9. punkoboy

    JustSayGo Guest

    The DVOM voltage checks prove that the battery has sufficient capibility
    under load and that battery capability is reaching the starter with an
    optimal ground connection.

    Most cars on the road will not pass each of these tests because of less
    than optimal connections.

    Once you know because you have proved with the DVOM that you have
    sufficient power and ground to the starter, what is value of starter
    draw info?

    If the engine still cranks slow with excellent connections between a
    good battery and the starter, either the starter is bad or the engine
    is too hard to turn because of mechanical problems. In either case
    starter draw will be beyond specs.

    These tests will diagnose the cause of any slow and most no cranking

    Perfoming these simple voltage tests and making repairs to high
    resistance connections on vehicles without any obvios problems, will
    increase reliability of every electrical component in the future.
    JustSayGo, Sep 14, 2006
  10. punkoboy

    DeserTBoB Guest

    Well, a good DMM with an accurate low resistance range will give you
    current draw anyway. All you have to get is the DC resistance to the
    same path of which you measure the voltage drop. Ohm's Law works
    every time: I = E/R.
    DeserTBoB, Sep 14, 2006
  11. punkoboy

    JustSayGo Guest

    I must be confused by reading your post. You can call it Digital Volt
    Ohm Meter or Digital Multi-Meter.

    Are you answering my simple question, "what is the value of measuring
    or knowing starter draw info?"

    How do you use a DMM to measure starter current draw to locate
    resistance? How do you test useing your low range resistance DMM to
    diagnose the problem?

    Ohms law formula is why the meter reads a differance from one point to
    the other whenever there is resistance.

    Measuring voltage at varios points under load is fast and simple. I
    don't need to measure or know the amount of resistance because voltage
    differance indicated by the volt meter will allow me to isolate the
    resistance and prove that my repair has corrected the problem. I don't
    need to measure starter draw to know if it is capable of performing its

    Measuring ohms of resistance without the load may not help in
    JustSayGo, Sep 15, 2006
  12. punkoboy

    DeserTBoB Guest

    Your procedure is the perfect way to locate a external high
    resistance, looking for high IR drops. The question was how to
    determine current draw, which in this case of troubleshooting, is
    irrelevant unless there is a weak or dragging motor, which may be the
    case here.

    Measure the point-to-point resistant from, say, the battery positive .
    terminal to the starter motor terminal in tenths of an ohm, more
    resolution if you have a Fluke or other good DMM. Then, measure the
    IR drop when the motor is cranking. Using Ohm's Law, simply divide the
    IR drop (voltage) by the circuit resistance, and you have the motor's
    current draw in amperes. What this WON'T show, of course, is high
    internal resistances in both the motor itself (bad brushes, burned
    commutator, etc.) and in the battery itself (low state of charge,
    sulfated plates, plate and strap corrosion, etc.)
    Exactly, and is also why you can easily calculate current draw if you
    know the external resistance, with the caveats stated above. Thus, if
    the IR drop between the battery and motor terminal side of the
    solenoid tested good, you'd want to know just how much that load of
    the motor is drawing. If current is low when IR drops are low, the
    trouble is either inside the motor itself, a "floating" ground (more
    common than most people realize) or a low or sulfated battery.
    Oh yes you do, if your IR drop tests prove there are no high
    resistances either in the positive cabling or in the ground circuit.
    If that's the case, and the motor current draw is low, the trouble's
    either the source (battery) or the load (motor.) A quick check of
    battery positive plate voltage under load will eliminate the battery
    in short order, and then proves the trouble into the motor housing
    The only change in resistance will occur when the load heats up the
    cabling, during which time the DC resistance of the cabling will
    increase somewhat. Bad connections, such as loose bolts and nuts, as
    well as battery terminals, will also heat up quickly during a high
    current draw, and are usually easy to spot by feel...if you dare.
    DeserTBoB, Sep 15, 2006
  13. punkoboy

    punkoboy Guest

    Thanks to all that have replied to my problem. After more checking,
    Took the surpintine belt off to check the pulleys and the alternator
    was locked up, stoping it from turning over. Learn something new every
    day. Thanks Again
    punkoboy, Sep 15, 2006
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