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How do you know if your starter is bad?

Is there some kind of test a auto shop can run on a starter to see if it's bad or going bad? I know you can test to see if an altanator is working right and if a battery is holding a charge, just wondered how you can figure out if a starter is bad?


  • edited October 2010
    Most auto parts stores can check the starter to see if its working. If the starter is bad you'll usually get a clicking sound or just a single click. A lot of times that click can be because the battery is drained as well
  • edited October 2010
    Do you have a car that is not starting? Normally you would have some more information. Does it ever start. Is there any noise when you turn the key? What does it sound like? How long have you had the problem, what make model year and mileage? Does it make any noise when you try to start it?

    So you think that is not an answer to your question. It really is. You tell is a starter is going bad by observing all the above and more. Experience helps out.

    A battery just stores energy and then gives it back. A starter does several things, like moving a gear into position so it can turn the engine. It also has to turn on a switch (solenoid).
  • edited October 2010
    Car started acting funny a week ago. Have had car for over 2 months with no issues, then last Sat when I went to start it, it sounded like it was hard to start, like battery low. Had batter tested, was told it was low on water, so filled. Drove van all week and no issues till friday when it again seemed hard to start. On Sat hooked up heavy duty battery charger for 5 hours, then went to battery place had it and alternator checked, was told both were fine. Went shopping, came out and went to start and nothing. No sound, no clicks no nothing. All dash lights came on like suppose to when I turned the key but nothing. Also last week when issue first occured I opened hood and got a faint smell of what smelled like burning wires. Well, since van didn't start, had it towed. Went back this morning to get something from van, tried to start it and it started like it should no issue. So could it be a bad starter? If battery/altanator are fine, what can cause car to sound like low battery/no ability to start but it comes and goes.
  • edited October 2010
    Thirty years ago we had equipment in the shop to test starters. Now, since the labor costs more than the new/rebuilt starter, if you take it out, there is no point in testing it because you would be silly to go to the trouble to put an old starter back in.

    The on-car test for the most common failure mode in a starter is: When it fails to crank, smack it with a broom handle or similar. If it cranks after being tapped, it is shot, replace it.
  • edited October 2010
    You can have a starter current draw test performed. This can be done with the starter motor in place.

    Find a shop that has an ammeter at a minimum (or an appropriate test meter) or a starter/alternator repair shop. The current draw will vary based on a number of factors; engine temp, engine wear, type of oil in the engine, etc.)

    The engine should be disabled to prevent it from starting. (remove the fuel pump relay, ECM fuse, etc.) When the engine is cranked over you should see (on average) about a 125-140 amp current draw during the steady cranking phase of this test.

    There will be a high current surge when the starter motor is first activated and this may be in the 300 or more amps range. This surge should only last a second or so.
    If the steady cranking current draw is up in the 175 amps or higher range the starter is likely failing; often due to worn bushings.
  • edited October 2010
    The starter is a strong electric motor with a spring loaded gear at the end of the shaft that comes out of the motor. A starter that cranks a long time, as in a motor that won't start, can get very hot. The heat melts some of the materials that make up the armature of the motor, or the wire windings. If there is enough heat and damage the armature can short out and the motor is dead.

    Many times a part of the armature goes bad due to heat and you have a "dead spot" in the motor. When the motor stops turning and it lands in the dead spot, it won't work - no nothing. This can respond to the "whack" test of hitting the motor with a hammer and the vibration can move things enough to get the current going and the motor seems to work fine. You could get several normal starts before hitting the dead spot again.

    The other way a starter fails is when the spring loaded gear gets so worn in won't engage the starter to the flywheel. This is noisey, the starter is spinning but the car's motor isn't getting spun and therefore won't start. Sometimes you hear a hum as the starter motor spins. Other times it is a loud grinding sound as the starter gear grinds against the flywheel but the teeth don't mesh together.

    It sounds like your starter falls into the dead spot category of failure.
  • edited October 2010
    What kind of life do starters have? Is it out of place for a starter that is over 8 years old and over 136,000 miles on the car to go bad?
  • edited October 2010
    I think you already know the answer to that question, starters fail with alot less miles/time on them. Just to make sure you are not missing something (this burned electrical smell is nothing to dismiss, it must be identified) check TSB's.
  • edited October 2010
    That owuld not be an abnormal failure at that life. The best way to test the starter is simply to check for applied voltage to the starter assembly when the failure is occurring. If you have 12 VDC and the starter isn't turning the engine over, then its the starter assembly.

    I'd agree with UncleT that it sounds like you have a bad winding or comutator segment except that were this the case you'd still normally hear the clicking of the solenoid when it's failing to start. I'd be more inclined to suspect either a poor cable connection or an intermittant ignition cylinder (the key cyinder). Or even a starter relay.

    Try researching TSBs for your year Kia Sedona. I seem to recall reading something about an intermittant starting problem, but without knowing your car's year it's tough to look up.
  • edited October 2010
    No TSB for starters. I read that when a starter does go bad you might get a whiff of what smells like burnt wires or plastic. Accorind to my mechanic who as never steered me wrong and after a full day of checking it is the starter and I am looking at $235 for new starter and labor. Starter is $155, labor 80. He said he it was bad and that after replacing it, the car started repeatedly without issue, as to before it would start 3-4 times then nothing, sit for a while, a slight tap on the starter and it would start again. He said if anything else comes up he will look at it and fix at no cost.
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