1988 - Starter Motor Energizes But Does Not Turn The Engine

[parkin]

Hello,

My 1988 Toyota Corolla (AE82) won't start and I hope somebody will have a suggestion

When I turn the ignition key the starter motor energises and engages with the flywheel but 99% of the time it does not have enough power to turn the engine. It acts like it would if the battery were almost flat. If I keep re-trying the ignition the starter motor sometimes manages to turn the engine and the engine starts and runs ok. Until I turn it off again and then the starter motor does the same thing all over again.

I've tried starting the car with jump leads from another car and the problem is the same, so I don't think it's a battery problem.

I've cleaned and re-made all the electrical connections from the battery to the starter solenoid, and from the ignition circuit to the relay, which is mounted on the case of the starter motor.

I've replaced the starter solenoid and motor with a secondhand one I bought on ebay. The problem is exactly the same. The motor energises but does not have enough grunt to turn the engine.

Any ideas would be very much appreciated.

parkin

 

[Scott O'Kashan]

Advance Auto Parts or Autozone will test the starter, alternator and battery for you for free so you can pinpoint the problem.

 

[parkin]

Thank you Scott, though we don't have those companies in Australia.

I don't believe it's the battery as I had exactly the same problem while connected to another car's battery (with its engine running) via jump leads.

And I've already replaced the starter motor and solenoid assembly.

Could the alternator prevent the starter motor from turning the engine?

parkin

 

[Scott O'Kashan]

I wasn't aware of your location, sorry mate. I would think any decent auto parts store would be willing to test the starter, alternator and battery for you in order to diagnose which of those is not doing it's job so they could sell you a replacement. It has to be one of those three, or a combination of them. If the battery has a short inside it, it wont conduct electricity and the engine wont start, no matter how much you try and charge the battery or jump start the engine from another vehicles battery. If you can't get an auto parts store to test the starting and charging system, try swapping in another battery temporarily to see if it makes any difference. If you turn on the headlights and radio, are the headlights bright and the radio sounding normally? If not, the battery is weak.

The alternator merely recharges the battery with electricity so the battery can turn the starter motor and get the engine started. Check the battery terminal connections where it clamps to the battery and make sure the surfaces are clean and shiny so they are making a good connection. If they aren't a wire brush or sandpaper will do the trick.

If the battery is a non-maintenance free battery and has six caps across the top of it, you can check to see if each of the six cells is full. Gently and slowly remove each cap one at a time. Please beware that below those caps is sulphuric acid which will burn your skin, destroy your clothes or blind you if it gets into your eyes. Do not hover your face over the caps as you remove them, because if there's any pressure under the cap, (it's possible), sulphuric acid can spray into your face and blind you. You want to slowly and gently remove each cap to avoid burns or worse. Have a bottle of water nearby so you can immediately rinse off any sulphuric acid that gets onto your hands and avoid acid burns.

After you have removed the battery cell caps, look into each cell with a flashlight and what you should see is the water and acid mixture inside each cell. The water should have a puckered look to it, barely touching the top edge of each cell. If any of the cells doesn't have that puckered look to the water, this means that cell is low on water and needs to be topped off. It is absolutely critical that only distilled water be used for this, as tap water or spring water will have minerals and/or chemicals in it that will shorten the batteries life.

How old is the battery? There should be a two digit code date sticker on the battery somewhere which reads something like, "A9", or something like that. This will tell us how old that battery is, unless you know, or the date chart on the top of the battery will tell us how old it is.

I hope this helps you out.

 

[Scott O'Kashan]

I'm curious; how are you making out with your car? Any progress?

 

[parkin]

I'm curious; how are you making out with your car? Any progress?

Hi Scott,

The car is still broken. I took the battery to the local auto-electrician. They tested it and said it was in good condition. I connected the battery directly to the (old) starter motor/solenoid on my patio using jump leads and the motor ran fine.

With the battery back in the car and connected up I activated the starter solenoid by applying +12V directly to the solenoid activation terminal. The starter motor engaged with the flywheel, energised but was not strong enough to turn the engine, but at least this ruled out the starter relay.

I ran heavy duty leads from the engine block to the -12V terminal and from the solenoid to the +12V terminal and the problem was still the same, but at least this ruled out the cabling.

I can turn the engine reasonably easily by hand using the finned disc on the alternator.

Today I think I will ask the auto-electrician to visit my home (I'm only 400 yards away from them) and do some professional troubleshooting.

I'll let you know.

Thanks,

parkin

 

[parkin]

The professional mechanic couldn't find anything wrong so he concluded that the problem is the starter motor, which is kind of annoying because I'd already figured that out for myself and bought a new (secondhand) starter motor off ebay and fitted it and still had exactly the same problem. What are the chances that both the original starter motor and the secondhand one have exactly the same fault? I'm not convinced. Anyway, the local garage is trying to make one good working starter motor out of the two of them.

parkin

 

[parkin]

My car is now fixed so I thought I'd let you all know what the problem was. Thanks for the suggestions but they were all wrong!

The mechanic dismantled the two dodgy starter motors and found that one of them had worn brushes (though probably not enough to stop it working) and the other had shaved its end-bearing into pieces (enough to stop it working). They replaced the bearing and serviced the motor and checked it on a test rig, and it was ok.

I installed the re-conditioned, known-to-be-working starter motor in my car and the original problem was still the same: when the ignition key was turned to crank the engine the solenoid engaged, the starter motor energised but the engine does not crank.

The real problem was the ignition key barrel contacts, which are worn. As you turn the key to the right the contacts close and the starter motor energises but as you continue to turn the key the contact runs off the worn end and the starter motor turns off again, even though the key is now in the fully clockwise position.

So the cheap fix is just to turn the key carefully (not all the way to the right) and the car is now starting every time.

Thanks for your help,

parkin

 

[Scott O'Kashan]

Wow.

Aren't cars, "fun"? lol

 

[johnster67]

Similar issue... but no luck yet

All,
I have a 2008 Corolla CE. Generally, no issues, but twice now, I have had a problem where the starter will engage, lights work, everything works, but it sounds like a bad starter or weak battery. I replaced the Battery, replaced the starter and solenoid, cleaned all the contacts, etc. I never had any luck. I pulled the headlight and dimmer relays, and swapped them, mistakenly thinking one was the starter relay. after I switched them, the car started. Yippee! Just the other day, it did the same thing. I pulled the fuse box under the hood, pulled off the bottom cover, then started the car, it fired right up. I put it all back together, and it would not start. When I went to measure the voltage drop across the battery, the car started. Now, I have no issues again. At no point did I get a check engine light, or anything similar. I am at a loss. I have not replaced the starter relay, as my big hands don't fit under the dash too well, and the problem seems to be under the hood, not interior. Any suggestions?