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Old 19th January 2009, 20:14   #1
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Starter Protection ?!!

While test driving Linea i noticed that when the engine stalled (the clutch was a bit sharp ), and when i turned the ignition, i couldn't turn it on till i turned the key to complete off position, before turning it on.

I have also noticed this in Logan. A friend tells me that turning the ignition on straight away will reduce the bettery life, though i am not sure about the reason. Why is this forced key turn to off position before turning on the ignition, when the engine stops?

Experts....Pls advice.
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Old 19th January 2009, 21:19   #2
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Linea has this advertised as a feature. It basically prevents the engine from being cranked again when its running. On cars which have highly refined engines, sometimes you won't be able to feel it running. Cranking it again is bad for the stater motor and the flywheel apparently. It has nothing to do with battery life.
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Old 19th January 2009, 21:23   #3
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My Ford Ikon had this feature too.
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Old 19th January 2009, 21:28   #4
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Originally Posted by nitrous View Post
My Ford Ikon had this feature too.
yes in fact if it's running and you try cranking, it won't crank but will be the equivalent of revving!
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Old 19th January 2009, 21:30   #5
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it is a safety feature. Like some cars do not crank unless the brake and in some cases the clutch is fully pressed.
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Old 20th January 2009, 11:39   #6
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Quote:
Originally Posted by oss View Post
While test driving Linea i noticed that when the engine stalled (the clutch was a bit sharp ), and when i turned the ignition, i couldn't turn it on till i turned the key to complete off position, before turning it on.
Useful feature. My Classic came with it back in '97! The purpose is to prevent damage / wear & tear to the starter.

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Originally Posted by iceman91 View Post
it is a safety feature. Like some cars do not crank unless the brake and in some cases the clutch is fully pressed.
How is it a safety feature? Worst case scenario in a car that doesn't have this type of ignition, the starter will crank despite the engine already running.
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Old 20th January 2009, 14:49   #7
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Originally Posted by GTO View Post
Useful feature. My Classic came with it back in '97! The purpose is to prevent damage / wear & tear to the starter.
Hmm. I do it often in my Swift Petrol, and realise when the starter motor makes that weird noise of trying to crank the already running engine.

Would this cause severe damage to the starter motor?
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Old 22nd January 2009, 16:02   #8
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Originally Posted by oss View Post
Hmm. I do it often in my Swift Petrol, and realise when the starter motor makes that weird noise of trying to crank the already running engine.

Would this cause severe damage to the starter motor?
Doing this often will ruin the starter motor/solenoid.
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Old 22nd January 2009, 16:27   #9
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Not just the starter motor - the flywheel has a ring / teeth to which the starter motor connects, and these teeth may break off, causing irreversible damage to your pocket.
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Old 22nd January 2009, 20:31   #10
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Originally Posted by BaCkSeAtDrIVeR View Post
Not just the starter motor - the flywheel has a ring / teeth to which the starter motor connects, and these teeth may break off, causing irreversible damage to your pocket.
Ah yes that's a point.

But a question here,

- Starter motor gear assembly disconnects the starter from the engine shaft after the engine is cranked and its running ? so until the engine stalls (i.e the flywheel stops moving) the starter motor should not be allowed to crank the engine.

i don't know how easy is it to implement such a system. Or it's already in place.

I think the "whirrrr" noise is due to the fact that the motor isnt under load and spinning at much faster rates (notice when you crank the speed of the motor is not that much) Also i'd add that running a motor without load is also bad for it.
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Old 22nd January 2009, 21:20   #11
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Quote:
Originally Posted by Xeno View Post
Ah yes that's a point.

But a question here,

- Starter motor gear assembly disconnects the starter from the engine shaft after the engine is cranked and its running ? so until the engine stalls (i.e the flywheel stops moving) the starter motor should not be allowed to crank the engine.

i don't know how easy is it to implement such a system. Or it's already in place.
that's what i mentioned earlier in this thread. on one ocassion i had music playing loud with the car in neutral (somehow i forgot this, thinking it was in gear). there i am pressing the pedal and wondering why i'm not moving! (couldn't hear the sound of the engine with the music on). so i try turning the ignition and it didn't give me that jarring sound i hear in marutis but was actually revving!

oh this is an ikon BTW.
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Old 22nd January 2009, 22:26   #12
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Quote:
Originally Posted by oss View Post
While test driving Linea i noticed that when the engine stalled (the clutch was a bit sharp ), and when i turned the ignition, i couldn't turn it on till i turned the key to complete off position, before turning it on.

I have also noticed this in Logan. A friend tells me that turning the ignition on straight away will reduce the bettery life, though i am not sure about the reason. Why is this forced key turn to off position before turning on the ignition, when the engine stops?

Experts....Pls advice.
FIAT has this feature in their cars and trucks(IVECO) from ages. you can even check it out in Palio.

Quote:
Originally Posted by Xeno View Post
But a question here,

- Starter motor gear assembly disconnects the starter from the engine shaft after the engine is cranked and its running ?

i don't know how easy is it to implement such a system. Or it's already in place.
such implementation is already in place. the starter motor is operated by the ECU. the starter is protected from all kinda of scenarios. and also the starter is controlled by the immobiliser. this feature is already there in TATA safari.
and regarding your question, in most of the old vehicles the starter will not be disconnected when you continously hold the ignition key ON. The engine driving the starter motor is prevented with the help of a free wheel mechanism.
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Old 23rd January 2009, 10:47   #13
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Quote:
Originally Posted by Xeno View Post
- Starter motor gear assembly disconnects the starter from the engine shaft after the engine is cranked and its running ? so until the engine stalls (i.e the flywheel stops moving) the starter motor should not be allowed to crank the engine.
Here is how a starter motor works.

1. You turn the key (or press the start button, as in some vehicles)
2. A "clutch" inside the motor pushes the rotor of the starter motor into the flywheel cogs, turning the flywheel; which in directly connected to the crankshaft.
3. You release the key / start button, and the rotor is pulled back by spring action, hence the engine is free.

If the rotor is not pushed into the flywheel at all, you will hear a "wheee" kind of sound - like in an electric mixer/grinder or vacuum cleaner. Something is wrong with the "clutch" assembly inside the starter motor. (Clutch is the term I am familiar with - you can name it anything else - :-) )

If you hear a "krr" sound when the engine is NOT working, it means the rotor has not been pushed into the flywheel properly - OR some teeth in the flywheel have broken and the rotor is not engaging the cogs of the flywheel properly. In this case, by simply playing around with the gears, and doing something to turn the engine slightly (releasing and holding the clutch again, etc) will cause the next cog in the flywheel come into place, and cranking the engine again.

If you cranik the engine while the engine is running - you will again hear a krr. sound - the starter motor would not engage the cogs of the flywheel, since even at idle, the flywheel would be spinning faster than the starter motor (I may be wrong on the relative speeds of the engine and starter motor). This uneven match of speeds damages both the flywheel and the motor.

The "double crank" protection - we are discussing in this thread prevents this kind of damage.

Going by description of this mecanism in other vehicles (Ikon and Fiat), I suspect this is achieved through circuitry in the ignition key, and ECU is not in the picture. I am not expert here though. I would love some confirmation on the matter.

Last edited by BaCkSeAtDrIVeR : 23rd January 2009 at 10:51.
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Old 23rd January 2009, 10:54   #14
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Quote:
Originally Posted by GTO View Post
How is it a safety feature? Worst case scenario in a car that doesn't have this type of ignition, the starter will crank despite the engine already running.
Car is in Gear you crank..what happens???
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Old 23rd January 2009, 11:08   #15
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I can understand not being able to crank when the engine is running. But when the engine stalls, why should one turn the whole thing off?
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