Make your own free website on Tripod.com



 

Do It Yourself - and save a fortune

There are two ways in which you can save big money on motoring costs.  The first is to buy an old banger instead of a new / nearly new car (which is what this site is all about).  The second is to carry out some or all of the servicing and repair work yourself.  Garage labour rates vary from £15 to as much as £70 per hour, and they make a profit on the parts they fit as well.  If you buy the parts yourself from the right place (click here for information on parts suppliers) and fit them yourself, then even if you have to buy some tools to start off with, you will save big money over the long run.

This guide is intended for people who have a reasonable amount of mechanical ability and understanding (i.e. they can wire up a mains plug without ending up in hospital, and put up a set of shelves without them falling off the wall the next day), but have never tackled DIY vehicle servicing and repair before.  It will cover the tools you need, where to get the technical information to help you repair your car, will cover in general terms some basic procedures that anyone can carry out, even with no experience, and give you some pointers to fault-finding and diagnosis.  But first, a few words about safety.  Please read this carefully - every year, people are killed or injured because they don't take safety seriously when working on vehicles.

The most important rule of all is this:  never, never, never work underneath your car unless it is properly supported on purpose built stands, placed under a strong part of the vehicle and positioned in such a way that they will not slip.  A vehicle supported by a jack is very unstable, and if the jack slips, the sight of the underside of your car falling towards your head will be the last thing you ever see.  Bricks are also unsuitable - they can fracture without warning, and a pile of bricks is even more unstable than a jack.  Axle stands are not expensive, and you can buy them from any motor accessory shop.  Always use them.

A motor vehicle contains a number of different fluids, all of which are dangerous in some way.  Petrol is highly inflammable, and can be ignited by a single spark caused when a steel spanner slips on a steel bolt.  Make sure the your work area is well ventilated, and if you accidentally spill some petrol, wait until the vapour has cleared before you do any more work on the vehicle.  Always keep a fire extinguisher handy - especially if your garage is built into the ground floor of your house....  Diesel and brake fluid also burn well, although they are harder to ignite.  Antifreeze is poisonous, and very attractive to pets, so don't leave old coolant sitting around in a bucket.  Screenwash will be either poisonous, or poisonous and flammable, depending on the type.  Old engine oil can cause skin cancer, so use a barrier cream or wear gloves when handling oily components.

Think of a car battery as a small bomb waiting to explode.  There is a lot of energy contained in that plastic box.  Always disconnect the battery when working on any electrical items, and never rest spanners or other metal tools on top of it - if you accidentally drop a spanner across the two terminals, the resulting explosion will cover you, your car and your garage in sulphuric acid.  Batteries can give off hydrogen gas, so no smoking anywhere near them, and don't do anything that might create large sparks.  If you have disconnected the battery, ensure that all the electrical items (headlights, ignition etc) are switched off before you reconnect it.  Finally, if you remove the battery from your vehicle, handle it carefully.  Don't tilt it, or you may end up with acid on your hands.  And place it very gently on a flat surface - the casing is quite brittle, and if you are rough with it you will have an acid spill to deal with, as well as a new battery to buy.

Don't lean over a running engine while wearing loose clothing, a large gold medallion or anything that might get caught up in the fan belt.  Seems obvious, but it's easy to forget. Don't touch any spark plug leads with the engine running - if you have a weak heart, this is a good way to find out.  Never unscrew the radiator cap on a warm engine without taking elaborate precautions, as you may be sprayed with boiling water.  Use a thick cloth to cover the cap and surrounding area, and unscrew it just a fraction of a turn at a time, to release the pressure gently.  And don't touch anything that may be hot, especially the exhaust system and brake components (immediately after a drive).

Avoid tackling jobs on safety-critical components, unless you are absolutely sure that (a) you understand how the component functions, (b) you have the necessary skills to work on it, and (c) you have the right tools for the job.  This applies to brakes, steering, suspension and fuel systems.  A bodge job in any of these areas may kill you.  Double check the tightness of all nuts and bolts in all of these areas when you have finished. 

Asbestos dust is a very nasty substance.  If you inhale it, it won't kill you immediately, but may do so a few years later.  Asbestos was banned from use in brake and clutch linings a few years ago, but you may still come across it, especially in older vehicles.  Don't blow the dust away with your mouth - brush it very gently, then wash it away with water.

Finally, use your common sense.  If you are doing something that feels unsafe, it probably is. 

 

Getting Tooled Up

Before you can do anything to your car, you need some tools.  Most of the tools you will buy can be used on any vehicle, and it is worth spending a bit extra to buy decent quality tools that will last a long time.  Beware the cheap Chinese tools which turn up at Sunday markets, car boot sales and discount shops.  These tend to be made from poor quality steel, and are likely to slip or even shatter under load.  You are much better buying good quality tools from a reputable company - British, German or American suppliers are the best.  You can often find good quality tools second hand at car boot sales and autojumbles - look for respected brand names such as Britool, Stanley, Elora, Snap-On, King Dick (!), Teng and Kamasa.  If a tool has no brand name on it, it is probably one of the cheap Chinese items referred to above.

Almost all cars built since the 1970s have used metric fasteners, although some British Leyland products continued to use imperial sizes into the 1980s.  The bolt sizes are measured across the flats of the bolt head, and many of the imperial sizes (known as 'AF') have a close metric equivalent.  So unless you have an elderly British banger, your best bet is to buy metric tools, and supplement them with any individual imperial sizes that you need.  As a guide, the following metric and AF sizes are interchangeable:

11mm - 7/16"

13mm - ½"

14mm - 9/16"

16mm - 5/8"

19mm - 3/4"

The most common fastener sizes on most cars are (in mm) 8, 10, 12, 13, 14, 15, 17, 19, 21, 24.  You should buy a socket set that covers these sizes.  Socket sets come in different sizes, depending on the size of the square drive used to fit the wrench to the socket.  ¼" drive is too feeble for automotive use.  3/8" drive will handle most jobs up to 15mm nut size, and ½" is suitable for heavier work.  A good socket set will have a mixture of 3/8" and ½" drive sockets, with appropriate wrenches, extension bars etc.  It will also have one or two spark plug sockets, about which more later.

You will also need some spanners.  These should cover the same range as the sockets, and the most versatile type is the 'combination' spanner, which has open jaws at one end and ring type jaws at the other.  These will cover most jobs, but it is worth buying a set of double ended offset ring spanners as well, as these will often get to bolt heads which are out of reach of a conventional spanner.

Some manufacturers make extensive use of unusual fasteners.  Ford are very fond of six-point Torx fasteners, VW tend to go for the twelve point version, and most manufacturers sometimes use Allen head bolts.  Peugeot occasionally use weird five sided socket screws to deter DIY mechanics.  If you come across these fasteners, you will need to buy the appropriate set of driver bits, unless your socket set is so comprehensive that it already contains them.  Don't try undoing these unusual fasteners using the wrong tool, as you will just round them off.  And with any socket head fastener, make sure you have cleaned all the dirt from the recess inside the head, and tap the bit carefully into the head before you try applying any force to it, to minimise the chance of damaging it.

A good set of screwdrivers is essential.  The ones with hardened tips are best (look for a matt finish to the tip).  Try to resist the temptation to use them for chiselling stuck components free, stirring paint or levering things, as they do not perform terribly well when they are bent or have chunks missing from the tip.

Pliers are handy things to have - one pair of square nose and one of needle nose should do nicely.  You won't actually use them that much, as they tend to round off bolt heads.  Much more useful is a pair of self grip pliers, generally known as Mole grips.  These have acquired a poor reputation, due partly to the proliferation of cheap foreign ones with chocolate jaws, but also because people tend to ask the impossible of them.  Good quality ones (like the American made Vise Grips) can be very useful for turning smooth shafts (such as steering shafts) or removing the remains of broken bolts, but they are not a substitute for the correct size spanner that you cannot find right now.

Axle stands I have already mentioned, and to go with them you need a decent jack.  The scissors jack normally provided by the manufacturers for wheel changing will just about lift the car, but can be awkward to position and operate.  Much better is a hydraulic trolley jack.  These can be bought for as little as £20 from car accessory shops, but don't expect a quality product at that price, and never trust the hydraulics even for a moment - as soon as you stop pumping the jack handle, put an axle stand underneath the car.  Trolley jacks only work on a smooth flat surface, so if you have a gravel drive, a bottle jack is a better bet, although it can be difficult to find enough clearance under the car to fit it.

For undoing wheel bolts, get yourself a decent wheel brace, and carry it in the car at all times.  Your chances of undoing the wheel bolts after a puncture, using the factory supplied item, are approximately nil.

Finally, you will need a work light.  You can buy 12 volt versions powered by the car battery, but the bulbs are quite expensive, and the light can only be used in areas within reach of the battery terminals.  Mains powered lights are much more versatile, and if the bulb blows you can nip into the house and 'borrow' a replacement, but if you don't have a garage with a power supply, you are stuck with the 12 volt lamp.

The above list covers the basic 'universal' tools:  there are other, more specialised tools that I will deal with under the job for which they are needed.

German reader Norbert Eichler sent me the following useful information:

"I strongly agree with your recommendation for quality tools, and would like to add a few names and own experiences.

"Out of the German brands, the best are Stahlwille and Hazet. Unsurpringsingly, they aren't exactly cheap. If you want to save, yet still demand good quality, you could go for Gedore, Rahsol and Proxxon. The Proxxon you find often in DIY markets like OBI (the German equivalent of B&Q), and they have a so called "industrial" line, which is pretty good, albeit not reaching the 2 top brands. Now France being closer to Britain than Germany, you might be interested to hear that Facom is very good as well. Switzerland's contribution is Kraftwerk. I bought a 1/4" socket set of theirs, and it feels very good. Didn't work with it yet, though.

"A very good source for tools is ebay. You can pick up virtually anything, and very often brand-new, at half the retail price or less. As my Granada I recently bought here came entirely without tools, and I feel a bit naked without the basics, I went around shopping here in UK as well. I found Stanley's quality pretty poor, at least on the screwdrivers they sell. (Editors note: Stanley, like other tool companies, have a number of different grades of product.  The stuff I have bought from them has been very good.) Draper seems to have different lines, and the "expert" looks pretty reasonable. The best seems to be Clarke's, but they also have different lines. Go for the ones with "lifetime warranty"

"I disagree with your notion that some AF tool could be replaced by metrics. If you deal with quality tools, as recommended, the tolerances of those are so tight that they won't fit the AF nuts and bolts. Yo could change that with the help of a good file (ruining that one in the process), but the you've spoiled the metric tools. I would really spent the few extra quid and go for equally good AF tools if needed."

 

Information

Mr Haynes is your new best friend.  If you plan to work on your own car, buy the appropriate Haynes workshop manual (£12 or thereabouts from almost any car accessory shop).  If there isn't a workshop manual available for your car, you are in some trouble, but this is very unlikely.  You can get further information from the Internet (try typing the make and model into a search engine such as Google, and see what comes up), or by joining a newsgroup (if there is one for your particular vehicle).  Avoid posting queries to newsgroups if they are the sort of simple question that could be resolved by reading the Haynes manual (e.g. 'How do I change the oil on a Ford Escort?') unless you want to know what 'flame' means in Internet-speak.  RTFM (Read The F****** Manual) should be your first line of attack.

 

Step One - the oil change

This is an ideal introduction to the world of DIY.  Any car will benefit from regular oil changes - for most older cars, an oil change every 5,000 miles is about right, with a full service at 10,000.  A successful oil change will give you the confidence to tackle other jobs, and will save you a few quid compared to having a garage do it.

For most cars, an oil change (with new filter) can be completed in less than 30 minutes.  You will need some oil (refer to handbook or workshop manual for quantity and specification), a new oil filter, a receptacle for draining the old oil, a suitable socket for undoing the plug in the bottom of the sump, and possibly a chain or strap wrench to unscrew the old oil filter.  Also, if the sump plug is fitted with a copper sealing washer (most are), this should be replaced with a new one at each oil change.

An oil change should be done with the engine warm.  Old engine oil is carcinogenic, so wear rubber gloves. Start by jacking up the front of the car and supporting it on axle stands, so that you can easily get to the sump plug.  Place sheets of old newspaper on the floor under the engine to soak up oil spills, and place a suitable container under the sump plug to catch the old oil.  An old washing up bowl is ideal for this, or you can use a plastic 5 litre oil container with a hole cut in the side.

Now unscrew the sump plug anti-clockwise.  You will probably find it is done up quite tightly, and you may need to use some force to get it undone.  Be careful not to pull the car off the axle stands in the process.  Make sure you are using the right socket or spanner for the job - if you round off the sump drain plug you are in trouble.  Six sided sockets are less likely to round off the corners than the more common twelve sided ones, and the wall-drive ('Metrinch') type are best of all.  Some cars use allen type plugs, or four sided recessed plugs, in which case you will need the appropriate drive socket.

Once the plug is loose, unscrew it the rest of the way by hand.  As soon as the plug comes free, hot oil will gush out, so make sure it doesn't go up your arm or on the floor, and don't drop the sump plug into the oil container.  Clean the sump plug with a cloth and put it to one side, and leave the oil to drain until only a few drops remain.  Inspect the sump plug carefully - if the head shows signs of being rounded off, it should be replaced to avoid future problems.

If there is a copper washer fitted to the sump plug, replace it with a new one.  Clean the area around the plug hole, and refit the plug.  Make sure you screw it in squarely and not cross-threaded - tighten it by hand to start with, and if it won't go in, don't force it unless you are sure it is correctly located on the threads.  Tighten the plug firmly, but don't overdo it or you might strip the thread in the plug hole - this is especially likely if your car has a cast aluminium sump.  Finally, wipe away any oil from around the sump plug, so you can see if it leaks when you put the fresh oil in.

Next, the oil filter.  This will almost certainly be a self contained canister type which screws onto the side of the engine block.  If you have any other type (such as the replaceable element filter on some old Triumphs and new Peugeots), refer to the workshop manual for details.  Canister filters can sometimes be unscrewed by hand - clean the outside first - but if you don't have a strong enough grip, there are two things you can try.  The best way is to use a proper strap or chain wrench to loosen the filter, but if you don't have one, just drive an old screwdriver straight through the filter body with a hammer, and use the screwdriver as a lever to unscrew the filter.  This is very messy and can be difficult on some cars where space is restricted, so I strongly advise the use of the correct tool.

Remember to position the container under the oil filter to catch the old oil.  Once you have unscrewed the filter, it will probably still be half full of oil, so turn it upside down and let the oil drain out.

The new filter will come with a sealing ring, which should be coated in fresh oil and pressed into the groove in the filter body.  Clean up the mating face on the cylinder block using a soft cloth, then screw on the new filter, tightening it as much as you can by hand.  Do not use tools to tighten it any further - hand tight is enough.  Again, wipe away any old oil from around the joint.

Now double check that you have refitted and tightened the sump plug.  I can guarantee that if you work on old cars for long enough, one day you will forget to refit the plug, and your new oil will go straight through the engine and onto the floor.  Remove the axle stands and lower the car to the ground.  Fill the engine with fresh oil to the 'Max' mark on the dipstick, checking regularly and wiping the dipstick with a cloth each time, before you take a reading.  Remember that it can take some time for cold oil to flow through the engine and into the sump, so don't accidentally overfill the engine.  Refit the oil filler cap.

You can now start it up.  Remember at this point that the system has been drained of oil, and the oil filter will need to fill up before any oil gets to the rest of the engine.  So don't touch the accelerator - let the engine fire up at idle.  The oil pressure warning light should go out within 5 seconds - if it does not extinguish after 10 seconds, stop the engine and recheck the oil level.  You may find that you read it incorrectly before, and there is not enough oil in the sump to reach the pickup pipe.

Once the oil pressure light goes out, you can relax, for the job is nearly done.  With the engine idling, check around the sump plug and oil filter for any signs of leakage - tighten further if needed.  Finally, stop the engine, let the oil settle for 5 minutes or so, and recheck the level on the dipstick.  Add further oil if needed to take it to the 'Max' level.  For this final check, ensure that the car is parked on level ground.

Remember to dispose of your old oil responsibly.  Decant it into a suitable container (such as an old oil can) and take it to the local council refuse dump, where there will be facilities for disposing of it.  Don't pour it down the drain, use it to light bonfires, try to kill the patch of nettles in the garden with it, or just leave it lying around in an open container waiting for you to trip over it.  The filter, once you have emptied the oil out of it, can go in the bin.

 

Step Two - spark plugs

On most modern cars, a full service consists of little more than an oil and filter change, and a new set of spark plugs.  Your Haynes manual will tell you what needs doing at each service.  However, if you have just bought a cheap old car, and want to ensure reliable starting, but don't feel confident or wealthy enough to attempt a full service, the best thing you can do is fit a new set of spark plugs.  These are often neglected on older cars, despite their low cost, and worn or faulty plugs will lead to difficult starting and rough running, especially in wet weather.  A spark plug change is very easy on most cars, requiring very little in the way of special tools, but there are a couple of points to catch out the novice, so read this guide first.

Tools - you will need a suitable spark plug spanner, and a set of feeler gauges.  Most cars use a 21mm plug spanner, but there are a few with much smaller spark plugs, such as 1.0 - 1.4 litre Peugeots and Citroens, for which a smaller spanner is needed.  If you have a socket set, there should be a suitable plug socket included in it.

Safety - car ignition systems use very high voltages, especially modern electronic ignition systems.  Do not touch any of the plug leads with your bare hands while the engine is running.  This especially applies if you have any kind of heart problem.  If for any reason you need to touch a 'live' plug lead, grip it with a clean, dry pair of pliers with insulated plastic handles.

Don't just rush straight in and take all the plugs out.  If you pull the leads off all the plugs at the same time, you will forget which lead goes to which cylinder, and the car will not start.  Replace one plug at a time, and refit the plug lead when you have done it.  Most bangers have readily accessible spark plugs, but on some engines you may have to remove a plastic cover to get to them.  Before removing the plug, try to clean out any dirt or oil which has accumulated around the base of the plug - you don't want it falling through the plug hole into the cylinder, if you can avoid it.

The plug should unscrew without too much trouble, unless it is a very long time since it was fitted.  Many engines now have aluminium cylinder heads, and if a plug corrodes into place, there is a risk that when you remove it you will destroy the thread in the plug hole.  This is bad news and very expensive to repair.  So if the plug doesn't come out fairly easily, screw it back in and take the car to a garage.  Once the plug has been removed, you can learn a fair bit from looking at it.  The Haynes manual has a selection of colour photos illustrating how plug colour and condition can reveal various engine problems.  Basically, if the plugs are a nice even light grey colour, all is well.  Anything else can indicate problems - although sooty black plugs will result from a very short journey with the choke out, and don't necessarily mean there is a problem.

Before fitting the new spark plug, you should set the plug gap in accordance with the manufacturer's recommendation (refer to workshop manual), using a feeler gauge.  Using a pair of fine nose pliers, gently bend the outer electrode until the correct size feeler gauge will just slip through the gap between inner and outer electrode.  I find that nowadays most makes of plug are pretty much spot on as supplied, and the gap size isn't absolutely critical anyway, especially as it will increase with use, as the centre electrode slowly gets eaten away.  If you don't have a workshop manual, set the gap to 0.7mm - this will work for pretty much any car.

The next bit is very important.  Spark plugs have a very fine thread, and it is easy to seat the plug incorrectly, so that it becomes 'cross threaded'.  If you attempt to use a plug spanner to tighten a cross threaded plug, it will destroy the thread in the plug hole - see above.  So the plug should initially be screwed in by hand if possible, until you are happy that it has engaged with the threads properly.  A new plug should screw in with very little resistance, unless the thread in the plug hole is already damaged.  Work slowly and gently at this point.  Once the plug is seated in the hole, it should be screwed in until resistance is felt, then tightened a little further to compress the sealing washer.  It must not be overtightened, or the delicate thread in the plug hole may strip.  Refer to the Haynes manual, or the box the plugs came in, for final tightening instructions - for most plugs it will be 'hand tight plus half a turn' or something similar, but some (mainly Ford) engines have taper seat plugs with no washer, and the procedure for these is different.

Once you have replaced all the plugs, double check that the plug leads are firmly in place, then start the engine and check it runs OK.  It is always worth doing this after any engine related job, however minor.  Otherwise, if you are doing several jobs, and at the end of it all the engine doesn't run properly, you won't know which bit you got wrong.  Finally, if the plug leads are covered in oil and dirt, clean them using a rag dipped in white spirit, and then wipe them dry.  You can do the same to the outside of the distributor cap and the top of the ignition coil.

 

More maintenance tips are on their way - keep checking the site for updates.