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Old 20th October 2009, 21:05   #646
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Default Please forget about re cambering leaf springs

As the topic states. You will find after a limited period of use the springs will once again loose their camber/temper.

If you intend to hold on to the vehicle, get a new set of leaves.
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Old 20th October 2009, 21:10   #647
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As the topic states. You will find after a limited period of use the springs will once again loose their camber/temper.

If you intend to hold on to the vehicle, get a new set of leaves.
At 2,10,000 kms, I am still on my original leaf spring assembly, but for a few replacements of broken leaves.
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Old 20th October 2009, 21:21   #648
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At 2,10,000 kms, I am still on my original leaf spring assembly, but for a few replacements of broken leaves.
Which again emphasises my point exactly. You got broken leaves "replaced", you did not recamber leaves that had lost their temper (not that you could!!!)

hvkumar about your springs doing 2.1L is a matter of driving conditions and maintainence. Leaves are known to loose their temper or crack/break. about the conditions of your older recambered leafs (cold hammering method) I am inclined to agree with anup. It is only a cosmetic change and could possibly be the reaosn for your springs breaking. I find it odd that a workshop would "forget" to refit bushes (spacers)!!!

Please reconsider your method. You could have a catastrophic failure and at a high speed that would be disastrous. Your leaves are the only thing attaching the axle to the body.

Last edited by Mohnish : 20th October 2009 at 21:30.
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Old 20th October 2009, 21:22   #649
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Cheaper to replace an occasional broken leaf than to change the entire assembly which is quite expensive. Leaf breakages are quite unusual.
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Old 20th October 2009, 21:33   #650
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Cheaper to replace an occasional broken leaf than to change the entire assembly which is quite expensive. Leaf breakages are quite unusual.
Yep! But in NIP's case, he believs the entire assembly is weak. Isn;t that why he is considering recambering/new set?
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Old 20th October 2009, 21:33   #651
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Cheaper to replace an occasional broken leaf than to change the entire assembly which is quite expensive. Leaf breakages are quite unusual.
...and yet you have been through 8 or 10??!!
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Old 20th October 2009, 21:35   #652
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...and yet you have been through 8 or 10??!!


Hi Anup, good to hear from you again...!!!
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Old 20th October 2009, 22:36   #653
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Mohnish, this 'fixing' or repairing of leaf springs is an old tradition in our country! In complete ignorance, all and sundry have re-cambered leaf springs with a modest hammer and at times a blow torch, ever since the advent of the first of our Indian automobiles like the Baby Hindustan and the Landmasters! I've seen this highly questionable practice for over five decades now!

Needless to say that with total absence of know-how and an unwillingness to adopt correct practices, the job was always a resounding failure! For a few days it did give the car a very impressive trim - amazingly wedge shaped, with the back standing proud by at least a foot! But in short order, within a few weeks, it would rapidly collapse under load and you had a car all ready for take-off! The front stood proud by a good foot!

Without the correct regimen of heat treatment it is futile to try and restore leaf springs to original glory.
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Old 20th October 2009, 22:57   #654
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Quote:
Originally Posted by hvkumar View Post
Leaf springs require to be recambered every 50-75K. The spring assembly is dismantled, the leaves hammered into shape, the bushes changed and refitted... No need to change any leaf unless it is broken.
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I'm doubtful about this procedure!
No hammering procedure can ever restore the spring qualities that leaf springs must possess!
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Standard operating procedure!... On one occasion, the M&M guys forgot to put the bushes in between the leaves and the resultant abrasion broke 5 springs at the same time!
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Indeed!
There is no way to 'cold service' leaf springs! Hammering achieves nothing but a cosmetic change!... If a stack or a bundle is in use the entire 'set' should be replaced.
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Originally Posted by Mohnish View Post
You will find after a limited period of use the springs will once again loose their camber/temper.
If you intend to hold on to the vehicle, get a new set of leaves.
Quote:
Originally Posted by hvkumar View Post
At 2,10,000 kms, I am still on my original leaf spring assembly, but for a few replacements of broken leaves.
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Originally Posted by Mohnish View Post
Which again emphasises my point exactly. You got broken leaves "replaced", you did not recamber leaves that had lost their temper (not that you could!!!)
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Originally Posted by hvkumar View Post
Cheaper to replace an occasional broken leaf than to change the entire assembly which is quite expensive. Leaf breakages are quite unusual.
Interesting ding-dong battle here about leaf spring repair/maintenance. If I may contribute my tuppence:

There is a method in how the spring patti repair shops (kamaniwallahs in Delhi lingo) handle the spring leaves. The spring leaves are usually NOT cold-hammered - they are heated to some extent (I think that's called annealing) to relieve the stresses, allowed to cool down somewhat, and THEN hammered into a greater curvature. The process of hammering restores some of the temper, without allowing the spring to crack. Cold-hammering, on the other hand, will invariably crack an already work-hardened leaf.

The shop also treats main leaf and the helper leaves differently. The main leaf is generally not hammered and re-cambered more than once or twice - whereas the helper leaves are subjected to more frequent attention. After one or two episodes of hammering, you are usually asked to replace the main patti (but not the helper leaves) - the guy knows how many times the main leaf has been subjected to hammering by the marks on it.

This is the way all leaf-sprung vehicles from trucks to Ambys have had their suspensions taken care of, and HVK's Scorpio is not any different. I've spent years in garages in the 80s, seeing just this job being done, and understanding why.

HVK's helper springs must have broken, not the main patti, else he'd most likely have been stranded, not driven to the service station. One or two broken helper pattis can get you back home (unless you are in Leh ), so no issues there. Kumar-saab, maybe you can confirm which leaf broke - main or helper.

As to nutcase mechanics who forget to put in the spacers between individual leaves, I've come across those too - and in today's "use and throw" world, replacing always sounds nicer than repairing.

Last edited by SS-Traveller : 20th October 2009 at 23:00.
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Old 20th October 2009, 23:36   #655
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Yes, SS, I was lucky to break only the "helper" spring no 3 which does not stop you from proceeding. I broke it somewhere near Rangdum, but repaired it only in Leh, which was 400 kms away.

In the earlier instance (when the spacers were not put in), I broke 5 springs (3 on LHS, 2 in RHS) in one go! That included the main spring also, but I managed to limp to the nearest M&M workshop, was very lucky on that occasion.

Unfortunately, in today's use-and-throw situation, the mechanics have also largely forgotten the heat-and-cool drill and even in M&M ASCs they merely reshape the leaves and reassemble them. During my Ladakh trip, I broke a leaf again by the time I reached Bombay, this was attributed to the leaves being of different "temper" and wrong spec!

The repairing of leaves has not been a bad thing at all in my case, although I see the merit in the arguments that have been put forth.
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Old 21st October 2009, 00:37   #656
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Mohnish, this 'fixing' or repairing of leaf springs is an old tradition in our country!...

...Without the correct regimen of heat treatment it is futile to try and restore leaf springs to original glory.
Completely agree with your entire post, more so the bold font above and in support of the same, the point I am making regards recambering / tempering metal is that the molecular structure of the metal changes with heat and knowing the exact amont required for a particular piece of metal in itself requires reasonable knowlegde of metals and then there is the question of actually heating it to the correct required temperature etc etc. Not something to be done with a blow torch...
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...
Again, agreed it has been in pratice and it has been done to earlier vehicles. It was done to a Maruti Omni many years back that my Dad owned. However, again I would not be comfortable knowing I am riding on a set of recambered leaves, much like riding on a set of retreads.

Possibly the reason for adopting this method was a cheaper quick apparent fix? Cabbies in Mumbai are doing this all the time and you regularly get the image Anup described of a cabbie parked in launch mode!
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...That included the main spring also, but I managed to limp to the nearest M&M workshop, was very lucky on that occasion...
You were lucky! Really lucky!
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...The repairing of leaves has not been a bad thing at all in my case, although I see the merit in the arguments that have been put forth.
Honestly, hvkumar I wonder if repairing of leaves has not been a bad thing at all in your case, considering the number of times you have had issues with the leaves. I have never till date had a broken leaf, though the Maruti I referred above did snap a leaf, maybe cause the leaves were recambered, like in your case.

To sum up: Without arguements with anyone, I am totally against recambering cold or hot. I would rather replace the set and get my self peace of mind. But I guess, to each their own!

Last edited by Mohnish : 21st October 2009 at 00:47.
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Old 21st October 2009, 10:00   #657
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Guys, today morning I found either someone has stolen the allow wheel cap, or broken it, I doubt about get it removed, as they are generally fixed from within, so looks like some broke it apart, I have not drive it for a long so and the last time i parked it I surely have seen that intact, let me know if anyone know it can be purchased from, I called service center and they replied not available and generally not in stock as they come fitted with vehicle and only 4 pieces are there ;-(

attached is the image for reference
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Mahindra Scorpio : Issues & Solutions-righttyre.png  

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Old 21st October 2009, 10:06   #658
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Sri Durga in Delhi usually have these in stock.
Rs. 300/- for the flat ones and 500 for the protruding ones. Each piece. You can buy per piece.

But how come the mounting hole is so jagged?
That should be a smooth circle.
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Old 21st October 2009, 10:09   #659
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Hello,

My trusted Tyre Dealer is offering me Imported Dunlop Tubeless Tyres for the Scorpio. These are 4200 each compared to 5200 for Bridgestore A/T. Does anybody have experience with the Dunlop tubeless tyres for the Scorpio ?

Styler

So has anybody used Dunlop Tubeless Tyres for the Scorpio ??
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Old 21st October 2009, 10:10   #660
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No that not the actual image, I just made it black to show on one of the image that I had on my PC, how can I get it from Delhi sir? I am in Nagpur any help here .

-Pramod
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