Saturday, August 7, 2010

OTHER TOOLS AND EQUIPMENT


If you intend to carry out a full body-off strip down prior to welding, a means of holding the chassis/floorpan at a comfortable working height is very useful. Strong steel trestles can easily be welded-up (good practice for the novice welder) and if two steel box sections are laid across these, you will have a solid and level platform onto which a few strong adults should easily be able to man-handle the assembly.
An angle grinder with cutting and grinding wheelsplus a sanding/linishing wheel and perhaps a cup brush will save hours of very hard work when you have to clean old paint. undcrseal or rust from metal. You will need a selection of tools for cutting sheet metal. such as tin snips. aviation shears (straight and curved)
Monodex cutter, hacksaw, sharp bolster chisel and lump hammer. Pneumatic chisels and air hacksaws which are powered by compressors are marvellous if your pocket runs to a large enough compressor to power them, because they allow you to cut body panels without the distortions which a holster chisel produces. The twin problems with the air chisel are its noise level (guaranteed to annoy neighbours) and its appetite for air, which can easily outstrip the capacity of smaller compressors.
Another very useful but incredibly noisy air ool is the descalcr. This tools uses air power to hammer a number of pins down onto a rusted surface, and can quickly remove all traces of rust and leave a surface
This small compressor provides enough compressed air to power an air chisel and other useful tools. It is a boon for the Beetle owner if only for its use in pressurising the windscreen washer bottle! It is useful for small paint spraying jobs, but for a full car respray you really need a compressor with a tank capacity ten or twenty times the 25 litres of the author's compressor, and a much more powerful motor.
ready for de-g- easing prior to welding or spraying. The noise level generated when working on a large, resonant
lief with either this tool or the air chisel, however, is
that the user must wear some form of hearing In some countries, laws will allow
neighbours the legal means to curtail such noisy activities. In the UK, noise is now treated as a form of pollution, and the authorities could be brought in by a neighbour if you were to make too much noise.
Speaking of compressors, these are incredibly useful, not merely for spraying, but for blowing rust and dust out of nooks and crannies. They are also useful to have to hand for blowing out minor welding fires which can start when paint, underseal or trim in the vicinity of the area being welded suddenly catches fire. Buy the largest compressor which you can afford, because very small units are quickly drained of air by certain attachments, and the motors have a short 'duty cycle' which causes them to shut off automatically to prevent them from overheating. This sometimes happens just as you really need them!
The author has also found that an old cylinder-type vacuum cleaner is one of the most useful tools in the workshop. Cleaning off an old bodyshell generates a tremendous amount of dust which, if you try to clear it with a broom, will mainly escape into the atmosphere only to re-settle elsewhere. If you are intending to spray paint in the near future then such dust will ruin the finish; if you are rebuilding a mechanical component then the dust will enter the 'works' and cause accelerated wear. The vacuum cleaner deals with this problem and is also useful for cleaning loose paint and rust flakes off the bodyshell, and for clearing filler dust from nooks and crannies before painting.
A pop-riveter is essential for fixing some items of trim but also very useful for positioning some panels prior to welding. Hand-powered pop rivet pliers are cheap to buy, and you should always look for a set which has long handles, because using them for any length of time can really make your hand ache! Air-powered alternatives are available, but it is up to the individual to decide whether the amount of pop riveting to be done justifies the extra cost of these.
The more ambitious restorer who wishes to fabricate some of the repair panels will benefit from a good set of panel beater's tools, although these can be very expensive and a rubber faced mallet plus a small selection of hammers and dollies can be substituted with some success. The author found a useful set of three planishing hammers and four dollies at VW Tools (address at the back of this book).

First steps with a MiG


Always practice on scrap metal and do not attempt any welding to the bodywork of your car until you are capable of producing consistently good results.
Safety is the most important consideration. If your workshop does not already possess one, then buy a fire extinguisher. Never weld in the vicinity of a petrol tank nor any other container which holds or has held combustible fluids, especially if the container is now empty or near-empty (an empty petrol tank contains more explosive fumes than a full one). Remember that paint, underseal and certain other materials to be found in a car (such as some sound-deadening material) can be flammable, and that many can be ignited by heat moving along a panel which is being welded. Keep a fire extinguisher handy for blowing out small welding fires.
Always use a proper welding mask. If you view the electric arc with the naked eye then you will later suffer an immensely painful phenomenon called arc eye. Arc eye is painful enough to drive most sufferers to seek hospital attention. The radiation given off by the MiG is not just harmful to eyes, but to skin as well, so always ensure that you are well protected.
Always wear protective clothing, especially strong leather gloves, and a hat (to prevent your hair from catching fire as the sparks shower) is a good idea. It is as well to wear old, thick items of clothing and stout leather shoes (red-hot weld splatter will burn through flimsy shoes and your sock — and when it reaches your foot it hurts like hell), as you will inevitably burn holes in most of them.
Never take liberties with the electric current, which is of a low voltage but quite powerful enough to kill you. Ensure that you weld only in dry conditions, and keep trailing leads off damp floors.
In MiG welding, an electric current passes down the MiG wire, melting both the end of the wire and the metal underneath it. so that the two fuse together. If the surface of the metal has any contaminants on it, including paint, rust or oil, then this will mix with the molten metal and weaken the joint. When welding typically thin car body steel, the steel panels become molten right through, and paint or other contaminants on the underside can be drawn up into the molten metal, again weakening the joint.
When first attempting to weld, try to run a bead onto a flat sheet of 18g or preferably 20g steel rather than attempting a joint between two pieces. Begin by cleaning the metal top and bottom thoroughly of all
rust, paint and grease. Trim the wire protruding from the MiG nozzle to around 10 mm. Place the earth clamp on the steel, put on all protective clothing then switch on the machine. Place the wire against the steel, pull the face visor in front of your eyes then press the trigger and begin to push or drag the gun along the surface of the steel, keeping the gun at an angle of around 70 degrees from the horizontal. Do not allow the mask to get too close to the weld, because sparks will quickly ruin it. Wrap-around face masks, particularly those which attach to the user's head, are recommended, because the alternative lollipop-type flat masks can allow in extraneous light from the top and sides which contract the pupils and make the viewed image of the welding process appear very dim.
When you first attempt to weld it will appear thateverything happens at once — sometimes too quickly foryou to establish gun movement before burning through begins. The solution is to keep on practising and adjusting the settings on the MiG to suit the steel you are welding until you master the art. The author is not possessed of particularly steady hands, and he has never found achieving good welds with the MiG an easy matter. The greatest problem is that of running the weld away from the intended join. He overcomes this problem to a great extent by resting the side of the MiG pistol grip against a solid object such as a length of scrap box section steel which is arranged so that it is in line with the intended join. Many people use proper head-mounted welding visors rather than the 'lollipop' type of mask typically supplied with cheaper welders, and this allows them to use their 'spare' (and heavily gloved) hand to help guide the MiG. Basically, the visor is tilted upwards so that the wearer can place the pistol grip onto the metal and support it using both hands (do not allow your hand too close to the 'business' end), then a flick of the head moves the visor downwards over the eyes, and welding can begin. Do not blame the author if you crick your neck trying this, though! The alternative is to wear MIG-proof goggles, but the author does not personally like these because radiation given off during a MiG welding session will tan your skin.
MiG 'plug' welding is an easy method of producing neat and strong joints. This simulates a spot weld, and is achieved by drilling holes in the uppermost of two panels which are to be joined, then clamping the panels tightly together and filling the holes with weld. The weld fuses to the bottom panel and to the side of the hole in the top panel. After surplus weld has been ground down, the results can be very neat and strong. However, do not use plug welds if you envisage ever having to remove the panel thus welded because, unlike spot welds, plug welds can turn out to be irregularly shaped and they cannot simply be drilled or cut out like spot welds. If you do elect to plug weld, the welds should be as frequent as the original spot welds which they are replacing.
Please check with your local vehicle testing authorities that plug welds are still acceptable for roadworthiness test purposes (MOT in the UK) before rebuilding your car using this technique. Although plug welds are perfectly acceptable at the time of writing, legislation does change and the author and publishers cannot be held accountable for future laws!
There are various types ofjoint which you will have to deal with. The butt joint is, as the name suggests, a join between two sheets of metal which butt against each other. A small gap should be left in between the two so that the weld can properly penetrate the joint, and the ideal tool for achieving this is the 'Inter-Grip'. This small device (sold in packs of five) can hold flat or curved panels tightly together for butt welding equally well. They are available from Frost Auto Restoration
Techniques (see address in rear of book). The author always tacks the two pieces of metal before continuously welding them, because if you start continuous welding at one end of the join and weld the whole lot in one go, distortion is very likely to occur.
Other joints include right angles (which can be difficult) and stepped joints (detailed in the following paragraph). Practice all types of joint because they will all be needed during a typical restoration.
A joddler (variously referred to as a 'joggler"jodder' and, more properly, as an edge setter) is a great aid. This tool places a step into the edge of a panel to allow it to overlap yet remain at the same level as the panel to which it is to be joined. The better joddlers incorporate a % in. punch, for punching holes in steel through which you can produce neat plug welds.
Two types of commercially manufactured joddler are commonly available. The less expensive is the scissors type, which can incorporate a plug weld hole punch.
The more expensive alternative works rather like a can opener and utilises two stepped wheels which are
pressed either side of the steel and then turned using a 'A in. ratchet drive as a winder. The author uses the scissors type, but found that the effort needed to step an edge into steel of greater thickness than 20g was too
high. He made up a cheap alternative using a large mole wrench, with two stepped blocks welded into the jaws (see photograph and illustration). The adjustable mole wrench allows pressure to be progressively built up as two or more passes are made over thick steel with the tool.
The joddled joint has a great advantage over the butt joint. Because the two halves of a joddled joint can be pulled tightly together and because the stepped edge of the joddled panel is parallel with the rest of the panel,
the two panels naturally tend to lie flat when they have been welded together. With the butt joint, it is easy to inadvertently weld the panels up so that they are not quite in line with each other. This becomes important when one of the two panels being joined is under any sort of stress. One instance which springs readily to mind is when a lower side (quarter) repair panel is being welded into position. The cutting process which removed the unwanted metal can easily have distorted the remaining metal. A joddled repair panel pulls this back into correct alignment when the panels are temporarily clamped with pop rivets or self tapping screws prior to welding.
If you have access to a spot welder, then you can utilise a useful alternative to joddled joints. By spot welding a strip of steel behind one edge so that it overlaps the other, you have a nice, flush joint to weld.
The alternative to doing the welding yourself is to bring in a skilled welder as and when required. There are many self-employed and mobile MiG and gas welders who may be hired by the hour, and they can usually be found listed in any commercial telephone directory.
When hiring a skilled welder it is as well to prepare as much work per visit as possible, otherwise the travelling expenses could eclipse the actual welding charges! For most DIY restorers who will only ever restore the one car, hiring a skilled welder is probably a better solution than learning to weld, because you will get better results and be able to drive your car safe in the knowledge that the welds will not spring open the first time you drive over a pot-hole!

By keeping the gun at a constant angle of seventy degrees, the molten weld is pushed as a 'wave' of sorts as the gun moves across the steel. This gives a more even bead.

Welding faults. Lack of penetration is usually caused by too low a power setting or too high a gun movement speed. Over penetration is vice versa. Contamination usually results in pores in the bead, and sometimes it merely causes spitting. In either case, the joint will be weakened. Burning through is a more extreme consequence of the factors which lead to over penetration — too high a power setting or, more commonly, thinned steel or too slow gun movement.

The corner joint can be welded from either the inside or the outside. If a folded lip is incorporated, then both inside and outside can be welded if desired, where extra rigidity is
required.


Different types of joint. Practice them all using scrap sheet steel before welding on your own car! The corner joint is made easier if one edge can have a folded lip.

Friday, August 6, 2010


Even more so than during mechanical repair work, a good workshop is highly recommended for body repair, restoration or customising work. Ideally, the workplace should allow you a bare minimum of one metre working area all around the car and, if you intend to separate the chassis and bodyshell (which is probable), you will need twice this area. If you have to carry out a full mechanical and trim strip down then do not under­estimate the amount of dry storage which will be required for the components.

A full bodyshell-off restoration


A full bodyshell-off restoration, Before starting work on a DIY restoration ask yourself whether your workshop, tools, skills and most importantly your commitment are up to the task ahead. Note: heater channels cut out of shell (internally braced), new channels bolted tofloorpans — Terry and Craig size up the task of lifting the shell onto the chassis.

Thursday, August 5, 2010

Using a MiG welder


The MiG is (apart from the spot welder) arguably the easiest of welding devices for the beginner to use for general bodywork repairs. This does not, however, mean that it is an easy matter to produce clean and strong welds on typically thin body panels for, unless conditions and the user's skills are both excellent, there are many obstacles to good welding.
The worst problem to beset the novice is that of 'burning through', when the electric current melts straight through the metal which it is supposed to be joining. This can occur if the wire feed speed is too slow (or intermittent, which indicates a fault in the welder — usually either the wire jamming in the liner or the driving wheels slipping), if the gun is moved across the metal too slowly, if the current is set too high or if the shielding gas/core fails to do its job.
When the metal to be welded has become thin through rusting then the chances of burning through are greatly increased, and hence the advice to always cut back to not only clean but also to strong and thick metal before attempting to weld.
The correct preparation of the metal which is to be welded is vital. All traces of rust, of paint, oil, grease and any other contaminant must be cleaned from the surface to avoid poor adhesion and spiting. Any impurities which find their way into the welded joint will substantially 11 Taken it.
When a joint is being welded, both surfaces should be thoroughly cleaned; if paint or any other contaminant is present on the underside of the panel then it will mix with the molten weld/steel and weaken the joint. Recently, special paints have become available which can be used on surfaces which are to be spot or MiG welded. The use of these products — such as 'Autoline' weldable zinc primer, will ensure that the welded joint does not — as is normal — become the first part of the repair to rust through again. The metal panels must then be clamped in some way so firmly that the heat of the welding process does not distort either of them and allow them to move apart. Small sections may be clamped using mole grips, although longer runs are usually affixed using self-tapping screws or alternatively pop rivets at regular intervals. the joint. Recently, special paints have become available which can be used on surfaces which are to be spot or MiG welded. The use of these products — such as 'Autoline' weldable zinc primer, will ensure that the welded joint does not — as is normal — become the first part of the repair to rust through again. The metal panels must then be clamped in some way so firmly that the heat of the welding process does not distort either of them and allow them to move apart. Small sections may be clamped using mole grips, although longer runs are usually affixed using self-tapping screws or alternatively pop rivets at regular intervals.

WELDING EQUIPMENT


There are four types of welding equipment which the DIY restorer might typically consider. These are Arc (often called 'Stick'), MiG, Gas and Spot welding equipment. Arc welding equipment is comparatively cheap to buy but has severe limitations regarding the thickness of metal it can be successfully used on. If the metal is less than '/.3 in. thick (i.e. all body panels) the fierce arc welder will quickly burn right through the metal which it is supposed to be joining! Arc welders are best suited to use on heavy section agricultural vehicle metal and are useless for the vast majority of car restoration work. An accessory called the Kel Arc Body Welder is available, however, which is claimed to cut the hot amps from the arc welder and to have a stitching motion which lifts the rod on and off the metal, allowing it to cool and preventing the rod from either sticking to or burning through the metal. The author has not had the opportunity to test this equipment. The costs of the Kel Arc attachment and an arc welder will still be slightly under the purchase price of a MiG welder.
The MiG (Metal Inert Gas) welder is the type normally used by the DIY restorer, and by the majority of professionals as well. It surrounds its electrode (in wire form) in an inert gas, so preventing the metal from burning through. It may therefore be used on the thin metal of car body panels. Two types are available. The more traditional MiG welder uses gas from either a small cylinder strapped to the unit or from a larger, remote cylinder, and different gasses are required for welding different metals. The newer type of MiG (the 'gasless' MiG which can only be used on steel) substitutes a substance contained as a core within the wire for the gas. Because large gas cylinders are expensive to buy, hire and fill and because small gas cylinders have to be replaced frequently at relatively high cost, this newer type of welder appears to offer advantages. The main advantage of the gasless MiG is that it possesses only one consumable (the cored wire) to run out ofl The MiG welder is probably the best type for a beginner.
The author uses a SIP 'Handymig' Gasless MiG welder; a unit which proved quite easy to use and which is capable of first-class results. The cored wire needed for a gasless welder is more expensive than that for a gas MiG, although because no gas need be purchased for the former, the running costs of the two will not differ greatly. As already stated, the fact that there is only the one consumable (the cored wire) to run out is very much in the gasless MiGs' favour, although the author has on occasions experienced difficulties in obtaining the specialised cored wire locally, whilst plain MiG wire is widely available. The cored wire is often (the author believes erroneously) referred to as 'flux cored'. It is essential that you are not inadvertently supplied with standard non-cored MiG wire for use with a gasless MiG, because without shielding gas, this will burn through body panels.
Gas welding is arguably the most versatile of all, and can produce excellent results in the hands of a skilled person. Arc, MiG and spot welders all use electricity to heat a very small area, whereas in gas welding a torch is used to heat both metal and welding rod, and a larger area of metal tends to become very hot as a result. The greatest drawback is that the heat which is necessary tends to warp body panels and can easily give a new panel a corrugated finish! Gas welding equipment can also be used for brazing and for heating stubborn nuts and bolts which refuse to move otherwise.
Spot welders are the easiest to use, although they are limited insofar as they can only be used (unless a range of quite expensive special arms are also available) for joining together the edges of two metal 'lips'. For such joins they give an unbeatable combination of ease of use, strength and neatness. No wire nor welding rod is required, because the spot welder uses electricity to heat and fuse two panels together. Few DIY restorers would go to the expense of buying a spot welder because of their limited applications, and most opt to hire them as and when necessary from a DIY store or tool hire business.
When using a spot welder two conditions are necessary for good results. Firstly, the two pieces of steel being joined must be tightly held together. Secondly, the surfaces must be spotlessly clean. It is nowadays normal practice to spray special zinc-based paints onto the metal before performing the weld, in order to reduce the chances of corrosion occurring.
Yet another accessory which has been available for the Arc welder for some time is claimed to allow users to spot weld two sheets of steel with access from one side alone, whereas the spot welder requires that one electrode is placed either side of the join. The Arc welder accessories have not been tested by the author, and while he cannot personally vouch for them he cannot see any reason why they should not work. It would be vital that the panels being joined were firmly clamped together in some way immediately either side of the single electrode, because the top layer would expand more rapidly due to heat than the underlying layer, so that the two would tend to move apart. Still on the subject of Arc welder accessories, kits are available which enable it to be used for brazing. Whilst the author has heard no comment detrimental to any of these Arc welder accessories, he has yet to find an experienced professional restorer who champions them.
Most welding equipment can only produce neat and strong results if the operator possesses the appropriate skills. The quickest way to acquire such skills is to enrol in a short welding course, perhaps an evening class at a college. Whilst it is true to say that you can teach yourself to weld, it is not recommended that you do so (especially using your own car as a guinea pig).
Because the MiG seems to be the type of welding equipment most commonly owned by the DIY restorer, an introduction to its use follows. If you wish to find out more then there are several excellent books available on the subject.

REPAIR AND RESTORATION BODYWORK


It is best to begin this chapter by stating that a full DIY car restoration is incredibly hard work and that very few people really appreciate just how much work is involved until they've either finished one or given up part-way through the job. Obviously, the amount of work needed in a restoration will depend on the original condition of the car and on the desired result; concourse cars can take many times as long as 'usable' cars. It is also dependant on the quality of the restoration; cut corners and you can bring the time requirement down — if you can live with second-class workmanship.
Whenever asked how long it takes to restore a car, the author's friend Em Fryer simply replies 'A year'. The best restorations can take thousands of hours; many run into years of part-time work. Many are never completed at all. Before embarking on a full restoration, therefore, you should consider very carefully whether your motivation (and funds) will be sufficient to last throughout the project. On the finance side, make as comprehensive as possible a list of necessary panels, mechanical components and consumables (paint, MiG wire etc.), and see whether the total is so high that you could obtain a better deal by simply selling your own car and buying one in better condition; the costs of even a DIY restoration often exceed the resultant value of the car!
You can cut costs by plating expensive pressingsrather than replacing them, i.e.. building up a floor edgefrom sheet steel rather than spending a lot of money ona proper repair panel or a full floor. The drawback withplating is that the car normally rusts through along theedges of welded seams and a car which is extensivelyplated can be expected to require more body repair worksooner than one which is largely re-panelled, if for noother reason than because the former has more seams!
You also need to honestly consider whether your own skills are sufficient for the job, because if you subsequently have to pay a professional restorer to put right your mistakes then his bill will probably be greater than that for a straight restoration. Many people appear to prefer to have bodywork and painting carried out by a professional, and then to undertake the mechanical build-up themselves.
One alternative to doing the whole job yourself is in effect to manage the restoration and to bring in a skilled mobile welder and perhaps a competent mechanic as and when required. This means that you undertake the donkey work such as the strip down, cutting out rotten metal, cleaning and so on, but that you can have confidence in the quality of the welding and of the mechanical build-up.
The author finds that decorating the workplace with photographs of the car being restored and of really nice examples of the same model can often provide that little extra inspiration needed to carry on working when
every fibre of his body is screaming to get out of the workshop! Whilst on the subject of photographs, it is worth keeping the fullest photographic record of any restoration; not only does this serve to prove that the car has in fact been restored should you ever wish to sell it, but it also shows the depth of the restoration.
Classic car restoration is often depicted in the many books and magazines on the subject to consist largely of cutting away rotten old panels and grafting in new, like a great surgeon heroically performing a life-saving operation. This is actually an important but neverthele;, relatively small part of the work encountered in car restoration. In fact, the bulk of the work of restoration b concerned with the far more humdrum business of cleaning. For every minute spent welding, there will usually be an hour or more of cleaning, ranging from scraping away old underseal, accumulated mud and rust from the underside of the car to cleaning burnt oil deposits and sundry dirt and gunge from engine and transmission components.
A large percentage of the restorer's time will also be spent in trying to establish and maintain a coherent and workable filing system' for the various components of the car. This is essential if you are not later to waste countless hours during the build-up in trying to find the as soon as (if not before) they are fitted, tools will quickly become rusted and new paintwork will suffer bloom. Good all-round lighting which illuminates the sides and underside of the car is essential, and a solid, level, crumble-proof concrete floor is absolutely vital. You will require plenty of dry storage for components. If you merely pile them up in a corner then rebuilding the car will be a nightmare because you will waste hours finding parts and many more hours cleaning rust from them if the area in which they have been stored is damp.
Some specialised tools and equipment are essential for restoration. Some form of welding equipment, if only a cheap MiG, is recommended— even if you intend to bring in an outside welder to carry out the bulk of the work, in order to allow you to tack panels into position for final welding up by the professional.

Heat exchangers and exhaust


Heat exchangers comprise a finned core which is contained within the body. Hot exhaust gasses passing through the core heat the fins which in turn heat the air which is forced through by the engine cooling fan. The heated air then passes through the heater channels to the interior of the car.
When replacing heat exchangers, as usual you have a choice between expensive original equipment components and spurious versions, Some of the latter may not have a large enough fin surface area, which reduces their efficiency at heating air considerably, so do bear this in mind when considering economies.
The exhaust is a low-cost item which is not really worth welded repair once it begins to blow (exhaust gasses escaping through a hole in the exhaust), because patches will be welded onto adjacent metal which will have thinned through rusting, and severe corrosion of these areas will usually occur very rapidly.

Generator

A dynamo is far less efficient and generates less electricity (perhaps as much as 60 per cent) than an alternator. If either is faulty, the author recommends that they are either taken to a specialist for renovation or exchanged, and that one of these courses of action is taken during a restoration.
When fitting a new-generator, it is advisable to also fit a new drive belt. (See Chapter Three for details of adjusting the belt tension.)

Starter motor


The starter motor needs a huge current because of the amount of energy required to turn the engine over. In the interests of safety, the ignition key does not have to handle this high power, but instead actuates a current which operates the starter solenoid. A solenoid is simply
a switch which is operated by a small electrical current, but which switches a circuit capable of carrying much higher currents.
The starter motor is a powerful electric motor which drives a gear which meshes with the teeth on the flywheel, turning the flywheel and hence the crankshaft. Competent electricians can carry out repairs to the motor, although exchange reconditioned units are recommended for the rest of us not so bright sparks. If the drive pinion teeth are damaged then the unit is also best replaced (in which case, the flywheel teeth will also be damaged).
The solenoid is mounted on the starter motor. Most problems with the unit occur because it sticks (which can often be cured with a sharp tap from the handle of a screwdriver), although other faults can occur. During the course of a full restoration it would be advisable to replace the starter motor and solenoid complete with professionally reconditioned alternatives.

Car wires are carried tightly bound in the loom. In order that you can, with the aid of a wiring diagram, trace which wires go where, the wires are colour coded. Many elderly cars have at some time been fitted with extra lengths of wire, either to replace damaged lengths or to power an extra device. Sometimes, the wires are of an appropriate colour and rating, but often they are not.
A damaged loom (frequently caused by welding too Close to the loom and melting off the insulation, often caused by shorting to earth which also burns off the insulation) is best replaced — even though looms are far from cheap to buy and anything but easy to install. Damaged individual lengths of wire outside the loom may be replaced with others of the same colour and diameter, except in cases where the damage is melted insulation and the wire runs into the loom, because the wire (and adjacent wires) in the loom could also have melted insulation.
Wire damage includes anything which bares the copper core or anything which reduces its effective internal cross sectional area, such as being pinched so that some of the strands of wire break but others survive. Check all visible wiring in the car for damage, and also check that spade and bullet connectors are insulated — it is not unknown for an un-insulated connector to drop off its terminal and start a fire.

Sunday, August 1, 2010

wiring diagram1



ELECTRICS

When the car is being driven, electricity is generated by either a dynamo (early cars) or an alternator (later models) driven by the crank pulley belt, and is used to provide energy to create a spark at the spark plugs, to operate the electrical equipment such as lights and wipers, and to keep the battery fully charged.
The battery provides a source of electricity to operate the starter motor, and to make up the shortfall in generated electricity when the car is on the move and demand exceeds the available supply.
The battery can provide a great deal of power, despite being 'only' 6 volt (early cars) or 12 volt, because it can provide a high amperage, or current. To help visualise just how much power a battery can generate, remember that it is possible — don't try this except to move the car to safety in an emergency — to move the car by placing it in gear and turning the engine over using the starter motor. In achieving this feat, the battery is supplying not only the energy needed to turn over the engine but also to physically move the car! One terminal of the battery is connected to earth; that is, to the bodyshell/chassis of the car, This allows every electrical device on the car to also be earthed, so that just one feed wire is needed to complete a circuit to the battery and provide power for the device concerned. Most electrical faults — incidentally — are caused by poor earthing, so always check the earth connection first. If a wire which is live (connected to the live terminal of the battery) touches any part Of the car which is earthed, current will flow through the wire to earth.
When the battery is connected to a circuit which has very little resistance (i.e., when it is shorted to earth through a wire) current passes through the wire at the battery's maximum amperage. Not even the meaty wire which connects the battery to the starter motor is capable of passing this current, and as a result the wire which shorts gets hot very quickly, burns off its insulation and an electrical fire ensues.
The ability of a wire to carry electricity safely is determined chiefly by its cross sectional area, and so wires which have to carry more current (starter motor feed. high-tension (spark plug) wires and to a much lesser extent the headlights) are thicker in section than wires which have only a small current to carry. The smaller the diameter of a wire, the more easily it catches fire if too high a current is passed through it.
To prevent wires carrying dangerously high currents through shorting to earth or some other electrical fault, mast circuits of cars are fitted with fuses. A fuse is a
short piece of un-insulated wire of a thickness design to melt if the current passing through it exceeds a ' certain level. In the interests of safety, the lights and
ignition are not normally fused though Beetle lighting systems usually are. Whenever a fuse blows, it is not a fault in itself but a symptom of a problem'elsewhere in its circuit. Most people simply replace blown fuses — sometimes with fuses of higher rating — but this-is a dangerous practice, because it allows too high a current to pass through the wiring which the fuse is intended to protect, and that wire could overheat and start an electrical fire because too highly rated a fuse has been fitted.
If a fuse blows, always trace the fault before fitting a new fuse. Never replace the fuse with one of a higher
. rating or worse with bits of tin foil — unless you enjoy being inside a burning car.
For the same reason, never add extra electrical devices to a fused circuit, Either the demand will outstrip the fuse's safety level causing it to blow or, if a higher rated fuse is foolishly fitted, it can cause a fire in the existing wiring if a fault develops. What is an electrical fire like? The author can answer this one — a minor incident, thankfully — from first-hand experience. Within a few seconds of a wire shorting to earth on a non-fused circuit, the insulation melts and begins to give off choking fumes which can fill the interior of a Beetle to the extent that you literally cannot see your hand in front of your face within maybe thirty seconds. If there are any combustible materials in the vicinity of the fire, these too will ignite from the heat and within a minute or two of the short to earth occurring the car could be full of flames in addition to smoke, which would by now have rendered any occupants of the car unconscious. If the fire includes brake fluid or fuel lines, the car will be a burnt-out shell in minutes.
What this is all leading to is the advice that, unless you are a qualified and experienced electrician, it is best to leave electrical problems and the fitting of extra electrical devices to an auto-electrician.
Restoration and electrics
Car wires are carried tightly bound in the loom. In order that you can, with the aid of a wiring diagram, trace which wires go where, the wires are colour coded. Many elderly cars have at some time been fitted with extra lengths of wire, either to replace damaged lengths or to power an extra device. Sometimes, the wires are of an appropriate colour and rating, but often they are not.
A damaged loom (frequently caused by welding too Close to the loom and melting off the insulation, often caused by shorting to earth which also burns off the insulation) is best replaced — even though looms are far from cheap to buy and anything but easy to install. Damaged individual lengths of wire outside the loom may be replaced with others of the same colour and diameter, except in cases where the damage is melted insulation and the wire runs into the loom, because the wire (and adjacent wires) in the loom could also have melted insulation.
Wire damage includes anything which bares the copper core or anything which reduces its effective internal cross sectional area, such as being pinched so that some of the strands of wire break but others survive. Check all visible wiring in the car for damage, and also check that spade and bullet connectors are insulated — it is not unknown for an un-insulated connector to drop off its terminal and start a fire.

Steering

Earlier cars have a steering box mounted on the front axle, 1302 (and 1302S) have the box mounted on the bodywork and the 1303 is fitted with rack and pinion steering again, mounted on the bodywork.
During a restoration, check the condition of the steering damper by pulling and pushing its arm in and out; if extra or less resistance is felt at any point in the travel, replace the damper. Also, feel for lost steering wheel movement; that is, movement of the perimeter of the steering wheel in excess of 1 in. which does not also turn the front wheels. If this is discovered, check whether there is play in any of the joints, including the track rod ends, before turning your attention to the steering box or rack.
In the case of the steering box, play between the worm and spindle axle can be dealt with by adjusting the screw (turn the steering to full lock and slacken the locknut first) on the front of the unit whilst the spindle is moved from side to side. If this fails to reduce void movement to the recommended level, the roller/worm play will have to be reduced.
Steering boxes can be adjusted to take up this void movement by slackening off the lock nut on the top of the unit, adjusting the screw (don't tighten it right up, but screw it in just until slight resistance is felt), then hold it in that position and tighten the locknut. Check that the steering is not tight before using the car on the road and, if it is, re-adjust the screw. If there is still too much void steering wheel travel, it is best to exchange the steering box.
The components of the worm and roller steering box. (Courtesy Autodata)
With steering racks, adjust the bolt situated under the rubber bung in the spare wheel well until it can just be felt to contact the thrust bearing — slackening then re­tightening the locknut accordingly.

The steering box



The later steering rack and associated components, This is the
left hand drive version, though the components are the same
as for the RHD version. (Courtesy Autodata)

1.Rack support bracket
2.Rack to bracket bolt
3.Rack pinion boot
4.Tie rod
5.Inner tie rod joint
6.Tie rod bracket
7.Steering rack box

8.Universal !obit shaft
9.Thrust pad
10.Thrust washer
11.Spring
12.Cover plate
13.Track rod end joint

the steering box



The steering box, tie rods and steering damper. Check the condition of the ball joints and damper during a restoration, and replace as necessary. (Courtesy Autodata)

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