Axles

Bringing a classic car back to a condition where it can be classed as roadworthy by the relevant authorities is a responsibility that cannot be taken lightly.  To put the vehicle back on the road means renewing or restoring to the underbody of the vehicle- in particular, its brakes, suspension with steering a priority.

If the vehicle being scrutinised before purchase is in running order, this is a significant advantage as the restorer will gain a clearer picture of the state of health of the vehicle's underbody.

The first item to test is the brakes.  Brakes in good order will mean that the car should stop smoothly with no fading (diminishing of stopping power), and it should track in a straight line.

 Any grinding or scraping noises will indicate that the brakes may be worn down past the linings and need to be replaced.

If the vehicle pulls to one side or the pedal goes down slowly, the hydraulic system may likely have sprung a leak.

A handy visual guide is to check the back of each wheel for signs of leaking brake fluid. Leaks can also be common around the master cylinder.

Next is to test the steering, and if possible, under a few different conditions. If the steering wheel starts to shudder severely at certain speeds, this is an almost sure sign that the front end will need a rebuild.

Excessive play in the steering wheel before the car starts to tum will mean that the steering linkage may be worn, or the steering box may need an overhaul.

If the vehicle is a "non-runner" that has been standing for many years, the restorer can safely assume that a major overhaul to all the underbody systems is on the cards. The fact that the vehicle is a non-runner should be considered in the seller's asking price.

It is a fact that while most amateur mechanics will know their way around an engine, a lot less will possess the necessary knowledge and experience to work on a vehicle's underbody.

A factor that will make it more or less certain than the task of renewing the three significant systems be placed in professional hands.

Most UK and European classic cars of the Fifties and the early Sixties came fitted with drum brakes in the front, which were considered cumbersome and outdated.

Unless the restorer is a stickler for authenticity, they will follow the trend to replace the drums with discs, which are so much better in many ways and will not cost a fortune to replace.

If the restorer has a large budget and intends to fit a more powerful engine, they should consider installing power-assisted brakes. However, it will be an unnecessary expense if the car's power is not to be increased.

The primary purpose of a car's suspension is to keep all four wheels on the road. Even if the vehicle is riding on the finest of tyres after the restoration, they will provide precious little in the way of roadholding if the suspension is not spot on.

If the model being restored is from the Sixties and sold in large quantities in its day, original replacements may still be available, although liable to be expensive.

If the model is more obscure , especially one that goes back to the Fifties, will be impossible to trace, and the only likely alternative will begin to source aftermarket parts.

There is no reason to panic as costs for aftermarkets parts are typically low, while quality is reasonably high.

The same procedures apply to the vehicle's shock absorbers. Going back to the pre-war years, hydraulic shock absorbers were popular and remained so until the Sixties. It was then that they were replaced by telescopic shock absorbers, which are popular today.

When a vehicle's wheel goes over a bump in the road, the suspension spring allows for adjustment allowing the vehicle floor to remain level.

The suspension spring provides essential movement for the wheels while the shock absorber act as a form of vibration damper for the spring.

Hardly any system connects the driver so directly to their vehicle than its steering.

A variety of mechanical solutions exist to make the car change direction as the driver wishes.

Hardly any system connects the driver so directly to their vehicle than its steering.

A variety of mechanical solutions exist to make the car change direction according to the driver's wishes.

Nearly all common types of steering follow the so-called 'Ackermann' principle, developed by the renowned German of hat same name more than two hundred years ago. The revolutionary principle behind the Ackermann theory is that the axle itself does not turn the vehicle,  instead the front wheels.

Hardly any system connects the driver so directly to their vehicle than its steering.

A variety of mechanical solutions exist to make the car change direction as the driver wishes.

Most European and UK cars of the Fifties and Sixties were fitted with rack and pinion steering.

Since in general use today, rack and pinion steering has consistently proved to be not only practical, compact as well as inexpensive to fit and maintain.

In smaller family saloons and sports tourers, there is no real reason to change anything, only to ensure that the system is in the best working condition.

Most larger saloons of the Fifties and Sixties were famous for their cumbersome steering.

Restorers who want to improve their driving experience often consider fitting power steering.

Power steering will dramatically improving their driving experience, especially if the car is driven in the city.

Once again, the fundamental decisions on how to bring the car's suspension up to the levels required to make it roadworthy and pleasant to drive will only really be taken in the workshop during the initial pre-renovation inspection.

The restoration project leader will need to bear in mind that the chances are that most of the underbody renovation will need to be farmed out to specialists and can be costly.

 

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My Classic Car Blog- All you need to know to acquire, restore and maintain a classic UK or European Car from the Fifties and Sixties

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Relative to the million plus new cars produced during the golden decades of the Fifties and Sixties, very few survived. After around a decade of being pushed to their limits under the testing UK and European winters, most of these cars were taken out of circulation.

Most were hauled off to the breakers yard with just a relative handful remaining stored in abandoned lock ups or under tarpaulins at the back of a field.  An absolute handful were  kept in a driveable condition- lovingly cared for by and gradually restored by devoted enthousiasts.

In the last twenty years or even more, an incredible surge in interest has grown up around classic cars and their restoration. While vehicles produced during the twentieth century have been improved dramtically, both in terms of appearance and technical capabilities, to many they lack the character of these vehicles, some of them produced more htna Seventy years ago.

To drive one of these cars means standing out from the crowd, through owning a vehicle that is truly unique, with the owner's personality stamped all over it

The goal of My Classic Car Blog is to provide those new to classic car restoration with an informative guide to help them plan their project, understand the stages involved, realise their limitations so they can avoid any pitfalls along the way.

Pitfalls that, if not handled properly and quickly, could cause the restoration project to be held up, not stay within budget, and even end in disaster.

We invite classic car restorers to look upon My Classic Car Blog as a kind of roadmap which, if  the advice given is followed closely, will lead the restorer to successfully complete their restoration project.

The major restoration procedures that need to be followed for UK and European Classic Car owners, but not necessarily in the order given are as follows:

*: including choosing the ideal classic car, establishing a workshop,  getting to know the vehicle, workshop health and safety, choosing tools and equipment,

*:  including the engine, gearbox, clutch, camshaft, carburettor, cooling system, cylinder head, driveshaft and exhaust system)

* including the axles, brakes, suspension, steering,

* including the alternator, battery, ignition coil, lighting, wiring, fuses, solenoids, starters, distributors and spark plugs.

* including treating rust, fabricating metal, panel beating, welding body metal,       

* including filling, masking, spraying paint,

* including wood trim, instrument panel, interior lights , steering wheel, dashboard ,

* including chrome trim, wood trim, mouldings, convertible tops, nameplates, number plates, emblems, windows, wire wheels,

* including repalcing carpets, carpet cleaning,

* including re-upholstery, fabric upholstery, vinyl upholstery, leather upholstery, armrests, door panels, headliners,

For the countless thousands that have completed a classic car restoration, for the many more that are currently working on one and especially for those considering restoring a classic in the future, My Classic Car Info will continue to provide history, tips, tricks, terminology and news on all aspects of the wonderful world of classic cars.

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My Classic Cars Blog- Restoring Axles

A vital component of any vehicle's underside are its front and rear axles.

Axles are central shafts connected to the wheels, moderating the engine's power to drive the car either forward or backwards.

With the notable exception of three-wheeled vehicles-   private and sports cars come with front and rear axles as standard.

In addition to turning the wheels, axles play another significant part in improving the vehicle's overall stability by supporting its weight.

There are two formats of axles-  "Live axles" and " Dead axles".

The rear axle does the hard work, delivering power to the driving wheels.

 In two parts, known as half shafts, connected through the differential, this common category of the rear axle is described as "live", as it rotates in line with the wheels of the vehicle.

The front axle shares the weight burden, as well as steering the vehicle. The front axles will also absorb any jolts suffered through being driven through less than perfect road surfaces.

 Because they have to deal with the unexpected, front axles are usually sturdier than the back, produced using either carbon or nickel steel.

The role of  the  front axle is simpler to  the rear - to  take its share in bearing the weight of the vehicle as well as facilitating its  steering and absorbing shocks caused by road surface variations.

Front axles usually fall into the "dead" category because they never rotate.

Specific models can be fitted with a live front axle, designed to transmit the vehicle's driving power through a transfer gearbox to the front wheels.

Some of Colin Chapman's early Lotuses used this design.

A live front axle differs from a dead front axle as it has insufficient strength and rigidity to carry the vehicle's weight.

The axle beam's ends are secured to short ( stub axles)  using kingpins to overcome this issue. Stub axles are produced using alloy steels containing chromium and molybdenum.

Axles are made up of two main segments- beams and track rods.

Axle Beams ( also known as rigid axles or solid axles) were the axle of choice in post-war UK and European cars, gradually replaced at the end of the Sixties by independent suspension. 

Comprising a single beam or shaft, the axle beam has the vehicle's wheels attached at either end by the  (king pin). This form of rigid axle was conducted by leaf springs or individual steering arms connected with the frame.

The advantage of the rigid style of axle design is its simple construction coupled with its ability to provide parallel guidance to the wheel.

What brought about its demise was the axle beam's considerable weight and bulk, making adding springs a challenging proposition.

Track rods are fitted to each end of the steering rack and adjusted to a preset tracking level. Consisting of an inner and outer track rod with the inner track rod attached to the steering rack and pinion while the outer track rod is connected to the steering knuckle on the wheel.

Track rod ends are flexible steering links in the form of a small ball joint connecting the tie rods to the steering knuckles that play a significant role in steering a vehicle.

In typical  Fifties and Sixties models, both the front and rear axles came fitted with constant-velocity ( CV) joints that made for smoother turns and driving on an uneven surface while boosting the car's acceleration capabilities.

When looking at a classic car with any eye for restoration, the potential problems  to look  for in the front and back axles include:
  • Wear in the track rod end ball joints is indicated if the vehicle's tires display a feathered wear pattern.
  • Loose track rods will cause excessive play, bad wheel alignment and substandard control. If, during a test drive, the car is challenging to steer, this is an indication that the track rods may need to be replaced.
  • If a  steady clicking, tapping or whirring noise can be heard as the vehicle accelerates or is cornering, it is an almost sure sign that the outer CV joint is faulty.

     

    If a loud clunking sound is heard as well as the clicking noise, it can be taken as read that the inner CV joint requires replacing.

The clunking and clinking noise is being caused by excessive movement of the CV joints.

Another sure sign that all is not right with a car's axle is when the driver experiences vibration when handling the steering wheel. These vibrations are a symptom of either a damaged or worn axle or CV joint  that is causing the axle assembly to move off-balance gradually.

Any problems or even mildest hint of possible problems with a vehicle's axles should never be ignored as they could rapidly render the car unstable and unsafe to drive.

As is the case a classic car's steering, brakes and suspension, where the vehicle's safety may be compromised, any diagnosis and subsequentrepair must be carried out by professionals who have the know-how and equipment to return the car to the position where it is completely roadworthy.

 

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