98 Suburban- bad ground, iffy starting

Discussion in 'Chevy Suburban Forum (GMC Yukon XL)' started by phoebeisis, Jun 28, 2009.

  1. phoebeisis

    phoebeisis Epic Member 5+ Years 1000 Posts

    I have a 1/2 ton 2wd 1998 Suburban. I've noticed for a while that if I TURN THE MOTOR OFF, but keep listening to the radio, it won't crank over very vigorously. It will always start, but the cranking is slow.

    Well, I got a new battery, but no real improvement.In fact, just now it cranked so slowly it barely started. Once running all is well, so I don't think it is the alternator.

    Could I have a bad ground? On most vehicles it is easy to find the ground wire- it comes off the battery, and is screwed to the frame or block somewhere. I don't see an obvious ground wire on the Suburban.

    When I changed the battery, I did put diaelectric grease on the battery terminal screws-could that have caused a problem. The stuff is non conducting, but I figured there would still be plenty of metal to metal contact?? Maybe I should clean it off?
    Do ground wires "go bad" on the Suburbans-typical 5.7 210,000 miles-runs great ?
    Which one is the ground wire?
    Thanks
    Charlie
     
  2. L0sts0ul

    L0sts0ul Rockstar 100 Posts

    sounds to me like a typical chevy problem. a dead spot on on the starter. I have seen this problem with more chevy 1/2 tons more than any other vehicle.

    as far as the dielectric grease, it is meant to conduct usually for spark plugs and things of that nature. I would clean it off your terminals though as it will help to collect dust and could cause problems later.
     
  3. L0sts0ul

    L0sts0ul Rockstar 100 Posts

    I forgot one thing, if you are concerned about your grounding, get a good multimeter that reads resistance, and put one lead to your negative terminal on your battery and set it to read resistance or impedance if you will, and then put the other lead to the point that it grounds on the frame. Then read it to the motor, and a few other GOOD grounding places on the frame to test it. You should be reading anything from 0 to 2 ohms MAX, if you get INF, or and infinity symbol, then you have a broken ground, but if your ground was broken then you wouldn't start at all, and your radio wouldn't even work.

    HTH
     
  4. phoebeisis

    phoebeisis Epic Member 5+ Years 1000 Posts

    Lost souls,
    Thanks for the tip. So a Chevy starters go bad in this way-a contact becomes worn and it barely cranks sometimes, but cranks ok at other times?

    Is the best cure just to buy a rebuilt starter- or is there an easy/cheap way to repair it?

    Thanks
    Charlie
     
  5. L0sts0ul

    L0sts0ul Rockstar 100 Posts

    usually the brushes on the starter motor tend to wear unevenly and that causes the dead spot. and it causes the "delayed" starting.

    Unless you are rebuilding to a high compression motor, or wanna pay the price for a brand new one, a rebuilt is usually the most cost effective and easiest way.
     
  6. ct9a

    ct9a Epic Member 5+ Years 1000 Posts

    This sounds exactly like what my burb has been doing the last couple of weeks. I'm not so sure my problem is the starter though, since when I go to crank it, my radio and climate control reset as though the battery was dead.
     
  7. phoebeisis

    phoebeisis Epic Member 5+ Years 1000 Posts

    I hate intermittent problems; it is so hard to figure out what is wrong.
    I guess I'll change the starter, and see what happens.

    Does anyone just replace the brushes- is that even possible anymore or do you have to drill out rivets etc. Usually it isn't worth half assed rebuilding it if it uses rivets and not bolts/screws.

    Thanks
    Charlie
     
  8. Jimmiee

    Jimmiee Epic Member 5+ Years 1000 Posts

    The easy to tell if your battery is bad is to turn on the headlights for 30 seconds. Turn them off and read your voltage with a volt meter. This is your base voltage.
    Also if you watch your volt meter while cranking the voltage should never drop more than 3 volts. If it does either the battery is low or the starter is ba,d providing all the cable connections are good.

    A good 12V battery will read 12.6 Volts.
    12.6 to 12.4 Volts is the OK range.
    Anything less than 12.4 is a warning that your battery needs either charging or replacement.

    12.6 = 100%
    12.4 = 75%
    12.2 = 25%
    12.0 = Dead

    The difference between a new battery and a dead battery is less that a volt! :)
     
  9. vncj96

    vncj96 Epic Member 5+ Years 1000 Posts

    I would start checking the main wires running tothe starter from the battery, corrosion can creep inside the insulation and this will rob you of a lot of cranking power, this happened on my college car and after two batteries I started looking for something else, new wires and the problem was gone. its cheap anyway to check so why not, could save you alot of money on unnecassary purchases.
     
  10. 2COR517

    2COR517 Epic Member 5+ Years 1000 Posts

    My recommendation also. I used to drive an old 87 plow truck that wouldn't start when it was hot. Replaced the starter-battery cable once it finally melted through. It fixed the problem. The big negative cable off the battery should go to either the frame, or usually the engine block. Trace it out, and clean the ends or just replace it. They are not that expensive.

    And definitely clean the excess dielectric grease of the terminals.
     

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