Please help me diagnose
10-14-12, 07:13 AM
#16
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What do you mean by a "bad engine" ? An "engine" does not go bad all of a sudden like that. Keep looking at what you did with the starting circuit. May be you blew a fuse (ignition, etc.) accidentally during your repair.
10-14-12, 07:16 AM
#17
The security system in our cars will still allow the starter to turn over, it just won't fire the engine.
Want to make sure the engine turns - simple enough, put a large ratchet or breaker bar on the front crank pulley and turn away... it should be hard to turn but should turn nonetheless... make sure you turn it the proper direction, which would be clockwise..
when you tested the starter, how did you do it? just on a bench with jump wires? You said you have 12+ volts at the starter? what about the start solenoid when cranking or trying to crank?
Also, perhaps the rest of the starter is bad, not just the contacts and perhaps it doesn't have enough torque to turn the motor...
Want to make sure the engine turns - simple enough, put a large ratchet or breaker bar on the front crank pulley and turn away... it should be hard to turn but should turn nonetheless... make sure you turn it the proper direction, which would be clockwise..
when you tested the starter, how did you do it? just on a bench with jump wires? You said you have 12+ volts at the starter? what about the start solenoid when cranking or trying to crank?
Also, perhaps the rest of the starter is bad, not just the contacts and perhaps it doesn't have enough torque to turn the motor...
10-14-12, 07:26 AM
#18
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I was referring to this post:
http://easyautodiagnostics.com/case_...ot_crank_1.php
http://easyautodiagnostics.com/case_...ot_crank_2.php
http://easyautodiagnostics.com/case_...ot_crank_3.php
http://easyautodiagnostics.com/case_...ot_crank_4.php
it's an old post, so there is no navigation. at 3rd, it mentioned about the engine lock up. That's why I was saying bad engine.
Yes, I agree with you, it shouldn't go back all of sudden.
The fuse you mentioned, which one could it be? What I understand is that:
1. I hear one click, that's means the ignition switch does send power to the starter.
2. I detected 12 V at the starter,
So I think there is no fuse involved. Am I wrong?
Thanks,
http://easyautodiagnostics.com/case_...ot_crank_1.php
http://easyautodiagnostics.com/case_...ot_crank_2.php
http://easyautodiagnostics.com/case_...ot_crank_3.php
http://easyautodiagnostics.com/case_...ot_crank_4.php
it's an old post, so there is no navigation. at 3rd, it mentioned about the engine lock up. That's why I was saying bad engine.
Yes, I agree with you, it shouldn't go back all of sudden.
The fuse you mentioned, which one could it be? What I understand is that:
1. I hear one click, that's means the ignition switch does send power to the starter.
2. I detected 12 V at the starter,
So I think there is no fuse involved. Am I wrong?
Thanks,
10-14-12, 07:30 AM
#19
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Thanks, man.
I will see if i can try the crank pulley.
For starter test, yes, just bench with jump wires. I did not check the solenoid (can't reach down there when it's in place)
Doesn't have torque to turn, that's a good possibility, but is there a way to confirm? Otherwise, I have to buy one to see if that's the case, which may be throwing money away.
I will see if i can try the crank pulley.
For starter test, yes, just bench with jump wires. I did not check the solenoid (can't reach down there when it's in place)
Doesn't have torque to turn, that's a good possibility, but is there a way to confirm? Otherwise, I have to buy one to see if that's the case, which may be throwing money away.
The security system in our cars will still allow the starter to turn over, it just won't fire the engine.
Want to make sure the engine turns - simple enough, put a large ratchet or breaker bar on the front crank pulley and turn away... it should be hard to turn but should turn nonetheless... make sure you turn it the proper direction, which would be clockwise..
when you tested the starter, how did you do it? just on a bench with jump wires? You said you have 12+ volts at the starter? what about the start solenoid when cranking or trying to crank?
Also, perhaps the rest of the starter is bad, not just the contacts and perhaps it doesn't have enough torque to turn the motor...
Want to make sure the engine turns - simple enough, put a large ratchet or breaker bar on the front crank pulley and turn away... it should be hard to turn but should turn nonetheless... make sure you turn it the proper direction, which would be clockwise..
when you tested the starter, how did you do it? just on a bench with jump wires? You said you have 12+ volts at the starter? what about the start solenoid when cranking or trying to crank?
Also, perhaps the rest of the starter is bad, not just the contacts and perhaps it doesn't have enough torque to turn the motor...
10-14-12, 07:42 AM
#20
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Help me understand your test. When you ran the starter with the battery, was it trying to turn the engine over or was it just spinning itself. This will make a huge difference in the amount of current it draws from the battery. You need to test it under load. When you say your wire resistance matched within 1 ohm, what exactly did you mean? If you have 1 ohm of resistance, there is no way the engine will crank over. I don't know how much you know about electricity but these two pieces of data are critical. If the starter is trying to turn over the engine it will be drawing the maximum amount of current from the battery. Any resistance in the wires between the battery and starter will cause the voltage at the starter to be less than the voltage at the battery. As per my previous post, if you had a 12 battery and the starter was demanding 100 amps and there was 1/10 ohm of resistance in the wiring then you will have 12-100/10=2volts at the starter. Obviously it won't start under these conditions. So you can see that the resistance must be so low that most of us couldn't even measure it with our digital multimeters. Since we can't measure resistance that small very easily, the voltage drop test is a good way to go. If you have two volt meters, put one on the battery posts and one on the starter posts. When you try to start the car the max current will be drawn and thus the max voltage drop between the two meters will occur. If you have more than about 1volt difference between the two meters I would say you have a corroded connection in one of the starter wires or possibly a bad ground.
10-14-12, 07:55 AM
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I did my test after I took it out. I basically laid it on the floor and connected it to the battery, and did the bench test. There is no engine load to it. And it spanned just fine.
The resistance part, I used a digital meter, and the readings changes around (I guess due to its sensitivity), but overall it's under 1 Ohm.
I will do a voltage drop test now. Will report back soon.
The resistance part, I used a digital meter, and the readings changes around (I guess due to its sensitivity), but overall it's under 1 Ohm.
I will do a voltage drop test now. Will report back soon.
Help me understand your test. When you ran the starter with the battery, was it trying to turn the engine over or was it just spinning itself. This will make a huge difference in the amount of current it draws from the battery. You need to test it under load. When you say your wire resistance matched within 1 ohm, what exactly did you mean? If you have 1 ohm of resistance, there is no way the engine will crank over. I don't know how much you know about electricity but these two pieces of data are critical. If the starter is trying to turn over the engine it will be drawing the maximum amount of current from the battery. Any resistance in the wires between the battery and starter will cause the voltage at the starter to be less than the voltage at the battery. As per my previous post, if you had a 12 battery and the starter was demanding 100 amps and there was 1/10 ohm of resistance in the wiring then you will have 12-100/10=2volts at the starter. Obviously it won't start under these conditions. So you can see that the resistance must be so low that most of us couldn't even measure it with our digital multimeters. Since we can't measure resistance that small very easily, the voltage drop test is a good way to go. If you have two volt meters, put one on the battery posts and one on the starter posts. When you try to start the car the max current will be drawn and thus the max voltage drop between the two meters will occur. If you have more than about 1volt difference between the two meters I would say you have a corroded connection in one of the starter wires or possibly a bad ground.
10-14-12, 08:16 AM
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Just did the voltage drop test, at the starter the voltage went from 12.3 V before turning ignition to about 1 V. So this sounds like a cable issue now. I plan to just replace that one cable (the positive cable split into two), will this work? If so, I will try it. (Never done this before, will have to see)
10-14-12, 08:43 AM
#24
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If you have the starter out, car parts shops can test the starter for you.
Salim
Salim
10-14-12, 09:52 AM
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Good news, guys,
I checked the power cable per Baekte, and guess what, one of the connector (splitter) has corroded and full of rust. I sprayed the battery terminal cleaner and brushed it thoroughly, then put it back in.
it started just like it did before. Happy again.
Want to thank each and everyone of you for your advises and suggestions from bottom of my heart. This has helped me a lot.
You guys have a great rest of Sunday. Enjoy the footballs.
I checked the power cable per Baekte, and guess what, one of the connector (splitter) has corroded and full of rust. I sprayed the battery terminal cleaner and brushed it thoroughly, then put it back in.
it started just like it did before. Happy again.Want to thank each and everyone of you for your advises and suggestions from bottom of my heart. This has helped me a lot.
You guys have a great rest of Sunday. Enjoy the footballs.
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