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Old 7th August 2008, 09:54   #16
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I thought we did that to avoid inconvenience to people walking by the car or to the car parking next to us!!!!
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Old 7th August 2008, 10:00   #17
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If you park your car with the steering wheel turned, the starter motor and battery would face more stress when the car is started.
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Old 7th August 2008, 10:06   #18
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Quote:
Originally Posted by vipul_singh View Post
If you park your car with the steering wheel turned, the starter motor and battery would face more stress when the car is started.
why??
starter motor not attached to steering rack or wheels IMO
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Old 7th August 2008, 10:11   #19
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Vikram, this mechanism was specifically engineered to provide a counter rebound upon turns, before that people used to turn but were not able to turn back straight and ended up in accidents.

Its by design and not due to unexpected forces.

Quote:
Originally Posted by vikram_d View Post
Ok. Let me see if I can explain this.

When you turn the steering, the steering column transfers that force onto the drive shaft and other related components to turn your wheels. So when you park with the wheels at an angle the steering parts exert an opposite force. Have you noticed how when you take a U Turn the steering tends to straighten out when you let go of yoru grip on it. This force is continously exerted on the steering column when you park with you wheels cross and not straight.

Last edited by dadu : 7th August 2008 at 10:12.
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Old 7th August 2008, 11:14   #20
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Quote:
Originally Posted by vipul_singh View Post
If you park your car with the steering wheel turned, the starter motor and battery would face more stress when the car is started.

No this would not happen as power steering (Whether electric or hydraulic) comes into action only when you turn the steering wheel. Position of steering wheel doesn't matter.
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Old 7th August 2008, 11:22   #21
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Whether it has an effect on mechanics or anything that you care, I always prefer to park with wheels straight or near about. This enables a more predictable response later when I reverse or go forward, and lesser shocks in case of over acceleration.
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Old 7th August 2008, 11:45   #22
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Quote:
Originally Posted by DieselFan View Post
No this would not happen as power steering (Whether electric or hydraulic) comes into action only when you turn the steering wheel. Position of steering wheel doesn't matter.
You are right. I got confused.
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Old 7th August 2008, 11:51   #23
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Quote:
Originally Posted by vasudeva View Post
Whether it has an effect on mechanics or anything that you care, I always prefer to park with wheels straight or near about. This enables a more predictable response later when I reverse or go forward, and lesser shocks in case of over acceleration.
generally speaking what you say is right.

However, there are situations you need to park with wheels either towards or away from the curb. especially while parking on a slope.
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Old 7th August 2008, 12:06   #24
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Quote:
Originally Posted by dadu View Post
Vikram, this mechanism was specifically engineered to provide a counter rebound upon turns, before that people used to turn but were not able to turn back straight and ended up in accidents.

Its by design and not due to unexpected forces.
I know it is by design and I never said it is unexpected. All I am trying to say is that the counter rebound is there even when a car is stationary and the wheel are not straight.

I dont know about other cars but at least in the swift when I turn full lock in any direction and then turn off ignition the steering tries to straighten out by a very small extent but it cant. This is the force I am talking about. Will have to try with other vehicles and check. Maybe people can try this on there cars and post those findings here.
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Old 7th August 2008, 12:40   #25
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As far as my understanding goes There are two types of Power steering present in the market. HYDRAULIC AND ELECTRIC. Swift comes with electris power steering while OHC and most of the cars with hydraulic power steering.
Now Hydraulic power steering is assisted with a hrdraulic pump which basically generating pressure and making it easier to turn the vehichle, also it is designed in such a way the it equlises pressure to keep it straight as soon as u done turning thats why the steering comes to zero position as soon as u leave it while the Car is running. in case of parking it as soon as u switch off the engine the pump stops and hence it become very difficult to turn the steering also it rest at the same position where u left it and oesnt comes to zero position by itself.ADVICE: ALWAYS TRY TO PARK UR CAR WITH POWER STEERING WITH STRAIGHT TYRES AS IF U LEAVE THE TYRES TURNED AND PARKED IT THERE ARE CHANCES OF POWER STEERING OIL LEAK SPECIALLY OLD CARS COS IN THIS WAY THE PRESSURE IS STILL THERE AND SEALS MIGHT LEAKS IF KEPT PRESSURISE FOR LONG.
In case of electric steering is also the same funda as once the ignition is off there is no supply for power steering sysytem, hence it comes to halt at same place where u left it.
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Old 7th August 2008, 14:07   #26
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Quote:
Originally Posted by vikram_d View Post
I know it is by design and I never said it is unexpected. All I am trying to say is that the counter rebound is there even when a car is stationary and the wheel are not straight.

I dont know about other cars but at least in the swift when I turn full lock in any direction and then turn off ignition the steering tries to straighten out by a very small extent but it cant. This is the force I am talking about. Will have to try with other vehicles and check. Maybe people can try this on there cars and post those findings here.
What you are saying is right Vikram but have you noticed that this happens in a stationary car irrespective of the engine being start or not and i guess this is because rubber being flexible, the tyres when turned are flexed negetively at the base which is in contact to the road surface with respect to the direction they originally stopped in due to which the the slight rebound but the steering mechanicals being stronger and wieight of the vehical do not allow the rubber to flex back completely to its original place.
This is evident by the circular marks left on the tyre base which was in contact with the road surface.
Try the following.
1.Overinflate the front tyres by 5-7psi and you will see the rebound is more, similarly less when the tyres are underinflated.
2.Stop the car with the tyres locked at full, but make sure the car was rolling when the steering is locked at full and the stop. Tyre pressure should be normal as usual . Now turn the steering straight, you will notice the rebound again.
This effect is not because of the counter rebound which occurs due to design and movement as others suggested rightly but due to the characteristics of rubber IMHO.

IMO if a vehicle is parked on level surface it would not matter if the wheels are turned in or straight as the weight is not biased and is being transferred to the suspensions and wheels when wheels are turned as it would if the wheels were straight.
But on inclines its different and hugely depends on which side the car is facing.
If the car is parked on a slope facing the incline side(north/up) then the weight of the vehicle is transferred to the rear wheels and suspensions, so if the steering is turned or straight it would'nt matter.
On the other hand if the car is facing the decline side(south/down) then the weight of the vehicle is transffered to the front suspension and wheels and also the steering mechanism and brakes as the dead weight wants to move forward and straight but the direction of the wheels force the weight to be transffered in the direction of the wheels, but since the vehicle is stationary and not moving, this creates an opposing force where the weight is trying to move straight and forward but is being stopped by the brakes and opposing direction of the wheels. So in this case it is better if the wheels are turned in straight and rocks or bricks placed in front of the wheels would stop the weight rolling. What this does is transfers the weight to the tyres which under stress can flex against the rocks thus reducing/minimising stress on the suspensions and steering mechanism.

PS: Sorry for the lost post but just my 2 cents.
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Old 7th August 2008, 14:32   #27
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I never gave much of a thought regarding the technical aspect. Considering the asthetical aspect, i prefer parking my car in a straight line. As a matter of fact, i ensure that it is straight almost every day wherever i park the car.

IMO,Wheel turned parking looks good for pictures.
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Old 7th August 2008, 15:18   #28
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Quote:
Originally Posted by mobike008 View Post
I never gave much of a thought regarding the technical aspect. Considering the asthetical aspect, i prefer parking my car in a straight line. As a matter of fact, i ensure that it is straight almost every day wherever i park the car.

IMO,Wheel turned parking looks good for pictures.

I turn in and park because i think people who would park close to my car can leave some distance besides it and not scratch my car.
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Old 8th August 2008, 00:59   #29
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Quote:
I dont know about other cars but at least in the swift when I turn full lock in any direction and then turn off ignition the steering tries to straighten out by a very small extent but it cant. This is the force I am talking about.
That is the effect of power steering switching on / off. You can also try this. Depress your brake, and start the engine. The brake pedal will give you a feed back, coz. brakes too are power assisted.
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Old 31st August 2010, 07:16   #30
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@mondymk3: Of course, what you say is right regarding the pressure aspect(and hence the leaking seals in older HPS units) but the wheels coming back to the original position has to do with the alignment parameters.
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