Some bits are easy, and some bits are not.
For instance, it's easy to check the lights, but how do you service the fridge?
I don't service it myself, I get someone competent to do it!
The same with all gas appliances. I'd rather pay £120, and rest assured that a qualified fitter has been over it, than risk the lives of my family and try to save that money.
Having said that, I recently had a chat about such fittings with the guy who came to service our gas fire. He is a CORGI qualified gas fitter and is certificated to work on cookers, fires, tumble dryers, and boilers that use compressed natural gas, or CNG.
He is NOT allowed to work on any appliance that uses LPG, or Liquid Petroleum Gas.
He explained that a seperate certificate was needed for each type of consumer, and to work on a caravan, a fitter needs one for LPG generally, lighting, boilers, fires, cookers, and fridges!
I just thought gas was gas!
Provided you're a reasonably competent mechanic, one of the easier jobs is to check the brakes.
Aside from a reasonable set of tools, you'll also need LMP (Low Melting Point) grease, agrease gun, a can of brake spray, Copperslip, latex gloves, Emery cloth, and a face mask.
Park the caravan solo on flat, level ground, apply the handbrake, and lower all the corner steadies.
Have a look at the hitch head. With an older 'van, if the hitch head is made of cast steel and painted an odd sort of creamy magnolia colour, you're probably looking at either a B&B or a Peak chassis. If it's an unpainted, pressed steel assembly, then it's more likely an AL-KO chassis.
Peak and B&B chassis' were used on virtually all British caravans up to about 1980, when AL-KO replaced them. AL-KO have been used on virtually all Continental 'vans for many years.
The construction and materials of the two heads differ, but their design and actions are very similar.
Basically, the housing is bolted to the tip of the 'A' frame and holds a double ended piston. The forrard end simply has a socket which attaches to the ball on the back of the tug, and the other end pushes a pivoting bar that applies the trailer brakes.
You may find that there is a fairing or shroud, over the hitch head, which needs to be removed first.
There are 3 grease nipples in the hitch head, one at the top, one at the back and one underneath. They must ALL be lubricated.
Follow the linkages along, and each time they encounter a pivot, give 'em a little dollop of LMP, making sure that it's rubbed well into the joints.
While you're there, with your can of LMP, have a look at the hitch head. If it has a small handle, whack a dollop of LMP in it, but if it's got a large (usually coloured red or green) unlocking handle, DO NOT lubricate it!
The head with the large handle indicates that it has a stabiliser, which is designed to stop the caravan swaying sideways.
Now to tackle the biggie, the brakes themselves.
Remove any wheeltrims, and then slacken, but do NOT remove, the wheel nuts.
The steadies are NOT designed to raise the 'van, but just to hold it in position. So, bung a proper jack under one side, jack it up, and chock it with axle stands. Then lower the corner steadies again. Keep the wheeltrims close to the wheel.
Put chocks front and aft of the wheel that's still on the ground, and remove the raised wheel. Then release the handbrake.
You must remember at this point that the drum may not have been off for a good long while, so do not try to hurry the task.
There are two methods of holding the drums on; there may be a screw through the drum into the hub, or there may be a single nut in the centre.
If there's a screw, you may need to resort to the use of an impact driver and a club hammer. After removing the screw, place it in the wheeltrim.
If there's a nut, there'll probably be a sort of castellated guard on it with a split-pin through it. Remove the split-pin, castellated guard, and nut, and place them in the wheeltrim. Then there will be a thick washer, place that in the wheeltrim too.
If there's a self-locking nut, go and buy two replacement nuts before continuing.
Have a grope around the back of the backplate and see if there's a brake adjuster. If there is, slacken it right off.
Tap sharply around the edge of the brake drum (if you hit it too hard, it'll crack!) until it dislodges. This may take some time, so spin the drum, give it half a turn, and clonk it again.
If the drum has a screw fitting, lift the drum away when it's loose. If the drum has a single nut on a central shaft, be very careful about taking it off. It's much heavier than it looks, and could 'drop' onto the stub axle, and either damage the axle or the seal. Also note that the bearings may fall out of the set-up.
There'll be a goodly amount of dust gumming things up, so give the whole thing a goodly squirt of brake spray. Do not be tempted to 'blow' the dust away, you'll end up inhaling it!
After the dust/spray has dissipated, have a good look at the brake shoes. You may wish to replace them. Before pulling them about, try drawing the layout. Pay attention to the lead-on and lead-off of the shoes (this will differ from side to side), and the location of the return springs. Then remove the shoe retainers, the return springs, and finally the shoes.
Any reasonable motor factor will be able to match the shoes, or you could pay top dollar and go to a caravan dealer for them.
On the other hand, you may want to just give the brake shoes a rub over with the Emery cloth. Don't forget to have a scrub around the brake drums, too!
Take a wire brush over the backplate, paying attention to all frictional surfaces and pivot points.
Wind the adjusters in and out as far as they'll go without damage, and give the threads and segments a smear of Copperslip. Don't forget the bits of thread behind the backplate!
During reassembly, lubricate all moving parts inside the drum with a thin smear of Copperslip, being careful to avoid getting any on the friction surfaces.
Replace the shoes. If you have a screw on drum, line it up and replace it.
If you have the bearings in the centre of the drum, stick your finger in and pull out some of the grease. If it looks and feels like soft marmalade, dollop it all over the bearings, if it's gone stiff like peanut butter, oik it all out. Pack the bearings with either good old, or new LMP grease.
Gently ease the drum back on, and then slide the outer bearing into place. Have a look in the grease cap to see what the contents are like. Grease does no good in the cap, it has to be on the bearings!
Replace the thick washer, and spin the nut onto the axle. Spin the drum, and tighten the nut until the drum resists turning, then slacken off about an eighth of a turn, just so the drum spins freely, but doesn't 'wobble'.
If you have a new self-lock nut, fit it as described above, and discard the old one.
Replace the castellated guard, rotating it so that a new split-pin may be inserted. Make sure that the ends are folded well back so they don't foul the edge of the drum, and replace the grease cap.
Apply the brake a few times to centralise the shoes and adjust the brakes, flip the brakes on a couple more times, and adjust again. You may need to do that a few times.
While the 'van is up, you may like to check the operation of the compensator. One of two methods may be used here; either rods or cables. The cables pull, but some of the rods push.
Begin by getting an assistant to gently push back on the hitch head, while you run from side to side spinning the wheels!
Most vans will auto-compensate, but unless your 'van is pulling to one side, the compensator won't need any adjustment.
Another little job is having a go at the jockey wheel. This is one item that is often overlooked, but does need attention! The Jockey wheel is a dirty great long screw thread in a tube, which fits into another tube, so that it may be wound up and down.
Wind the front of the 'van up as high as possible with the jockey wheel, and set all the corner steadies. Wind the jockey down a bit to take the weight off, and unclamp it. Lift it as high as possible in its clamp, and wind it down. Eventually, the lower portion should drop out.
You may find it easier to take the whole thing off the front of the caravan, and enlist the aid of an assistant (or a vice!)
When it's in bits, clear out anything that shouldn't be in there, like small bits of swarf, grit, dead spiders, etc. Put a dollop of LMP on the end of the thread, and another in the wheel end.
Does the wheel spin freely? A simple nut and bolt hold the wheel on, so you may wish to take them apart and clean that end up, too.
Assemble the two parts of tube, and then put the assembly back into it's clamp.
If you plan to do anything with the electrics, please be advised that there are several individual circuits.
One is for road lighting, another is the internal 12-volts, and there is also the 240-volt circuit. Part of the internal 12-volt system is supplied by the tug, and part is supplied by the 240-volt site hook-up, and some of these bits overlap!
The fridge, for instance, can be a 3-way unit, and can run on gas, 12-volts or 240-volts. The electric water pump(s) may be 12 volts, but the shower can be either 12 or 240-volt.
Dependant upon the way the installation was completed, the mains runs a charger to keep the battery topped-up, the fridge, shower, maybe 2 or 3 13 amp outlets, and possibly a couple of interior lights.
If part of this complex system breaks down, you'll need specialist equipment and knowledge to resurrect it!
If you need to replace it, go for a reasonable branded leisure battery. A leisure battery is designed to be run almost flat and then charged to capacity, almost on a daily basis, whereas if an ordinary car battery is run flat, the plates will buckle. The cost of a purpose made battery is maybe twice that of the ordinary one, but it could last 5 or 6 seasons!
The only other 'user-servicable' parts are the light bulbs! The road light bulbs are the same as would be used in a car, so no difficulty there. Older trailers will almost certainly have the Maypole style of lights. These are lightweight, inexpensive additional units that manufacturers supplied until about 1995. The lens is held on by two screws, and once removed, the bulbs are easily removed.
I said that a little glibly, as I once had a 15-year-old caravan that had never had the lenses taken off!
The lights seemed dim, and eventually a brake light went. I took the unit apart, and could easily see that if I were able to get the old, rusted bulb out, I'd be hard pushed to get another to fit it! I took the other lens off and realised that the lights had been filling up with water and not draining. I gave the bulb bases a good soaking with WD-40, and bunged the lenses in warm soapy water!
I was only partly successful in replacing the bulbs, as the light bases were badly corroded. The dimness of the lights was only partly due to the manky lenses. The slightly dodgy connection was also responsible for some of it.
The only answer was to replace the complete light units, but that's another story!
Special care must be paid to the tyres. These manage to become a 'distress purchase' every so often! In accordance with the law, each tyre must be free from splits, cracks or bulges, correctly inflated, and also have at least 2mm of tread over 3/4 of its width around it's entire circumference.
Under normal circumstances, caravan tyres rarely wear out. What usually happens is that because the 'van is sitting in one spot for the bulk of its life, the sidewalls will start to disintegrate. Evidence of this will be tiny little hairline cracks appearing down the sides. Eventually, the tyre will fail, and we don't need that at 60 mph in the middle of the M6!
If you need to replace a tyre, try and get proper caravan tyres, or at least 6-ply or commercial rated tyre. Ordinary car tyres are just not enough! Any good tyre dealer will help out sensibly.
All sorts of caravan and camping-related information can be found at http://www.clicreports.co.uk (or http://www.eclipse.co.uk/samwise)
