starter motor or alternator? car won't start?

Question

my car will not start, but will with a little push. the aa said it was the battery, so got new one and car worked for 2 weeks but now its not starting again. called a.a. again they now say starter motor drawing 345 amp while cranking and turning slowly???? some times it will start. What do i need to buy to fix this problem

my car is a renault twingo year 2000

Answer 1

Start the engine.

Whilst the engine is running disconnect the battery earth lead.

If the engine cuts out then the alternator is faulty.

If the alternator is in order,reconnect the battery and place a jump lead from any place on the engine block to a good earthing point on the body.Try starting the engine.If it starts well, then check form damaged or worn earth strap from engine to body.

It is of course possible that the starter is faulty,this may also be contributing to draining the battery heavily during starting.

You will be able to get a free battery/alternator test from most motor factor shops.eliminating one or both of these from the equation.

Answer 2

no, no and no.
-disconnecting the "earth" tells you nothing.
-parts guys are not mechanics.
-neither are most of the people on here
- putting a voltmeter across a battery terminals will not tell you how much current is being drawn.

with that said, 345 amps is very high starter draw. most likely a bad starter motor there, or a mechanical problem with the engine.
(meaning the engine is too hard to turn over, requiring more amps to get the job done, not very likely). A bad ground (or "earth", omg), dead battery as a result of alternator, etc. etc. will result in low current draw.
to test the alternator, put a voltmeter on the battery and look at the VOLTS. not current, unless you want a melted meter. 13.5 volts or better while running generally is good. theres more than this to it, but you may want to see a mechanic beyond this point, especially after reading these answers.

Answer 3

its either your starter, alternator or bad ground, or locked up bearings in an accessory. anyone of these will cause your problem. make sure battery cables are clean and tight on battery and make sure negative on block is clean and tight. check with multimeter for 13-15 volts while running like above post states. if you have this your alternator is probably good (not always as amps push volts not the other way around) but its usually correct. take a thick wire and wrap it (stripped) around your negative battery post and touch the other end stripped to your starter ( it wont hurt you as long as your only touching the wire) and have someone crank it, if you still have a slow starting problem. take your belts off and spin each pulley with your hand none except your crank pulley should be hard to turn, if so then that accessory has bad bearings. if all above check out the starter probably bad. good luck

Answer 4

test the alternator simply . first though you need the engine running , so hopefully you can start it this time . do this at night , turn the lights on full beam , rev the engine and if the lights go brighter with the rev increase , then the alternator is doing it's job . if not , i would say the alternator isn't charging the battery and you had 2 weeks of new battery power until it ran down . after saying all this i would go for a replacement starter motor ,. if you have a local electrical engineers they can test it , but my hunch is go ahead and replace it , possibly 2nd hand from a breakers . do the alternator test first though to rule it out. good luck , dave .

Answer 5

could be the alternator as this charges the battery. once its started try going for a long run maybe 50miles. get break down cover in case you break down. Another common problem is the solenoid which is a smaller cylinder thing on top of starter motor if you bang that with a hammer this might start the car. Then you ll know its the solenoid that needs replacing. If youve got break down cover call them out anyway if the car wont start and you get a second opinion on what the problem is.

Answer 6

If your car, once going, doesn't die half way down the street you're driving on, then it is NOT your alternator.

You didn't mention what kinda car, but if it's pulling 345 amp then it had better be a porsche.

Get a new starter - depending on your car, go to a junkyard and lots of cars that have been written off have excellent internal parts.

Get the schematics (plans) of your car, and actually a starter is pretty kewl to fix on your own. If you wish to pay a mechanic, bring the part in and ask them to install. Maximum (and get a written estimate) should be about 1.5 hours.

Good luck and good question.

Answer 7

Sounds like your alternator isnt charging the battery up enough to power the starter motor. it probably started for 2 weeks because the battery was fully charged and didnt need charging. have the alternator serviced. should cost around 200-300 bucks

Answer 8

Sounds like a charging problem - possibly the alternator.

If it started with the new battery then it is not the starter motor so ignore all of those silly answers.

The best way to check will be with a multi meter - put it accross the battery with the car off and see what current is being drawn. If there is a current something electrical is faulty or shorting and causing your battery to drain

If there is Zero current being drawn or very low then its your Alternator.

Don't take it to a Renault dealer!

Answer 9

Make sure you have a fully charged battery, and all the cables are fitted tightly. If the battery is recharged, and you have problems starting, a reconditioned starter motor will fix it. These are cheap and easy to replace in most cars.

Answer 10

Could be a problem with the alternator/charging system. Have a person who specializes in battery and alternator service check it out. I was going to give the adivice Private, gave, but you run the risk of explosion of the battery. This is my quick test too.