WHEEL CHECKS

Recent occurrences have prompted me to mention how important it is to carefully and regularly examine your classic’s road wheels. It’s true that they usually survive for decades before serious trouble is likely. Equally though, if a car has often been used in harsh winter conditions, or has been standing unused for a very long period, rusting of wheel structures can become a serious and potentially dangerous issue.

In two cases I have heard about, a road wheel on a classic car has collapsed due to corrosion while the vehicle was being driven. Fortunately in each case nobody was hurt, and serious damage to the vehicle was avoided. Both owners had been unaware of just how weak their wheels had become, but it’s important to appreciate that when a wheel does give way, it usually does so very suddenly, and without any prior warning.

Like any vehicle component made from steel, wheels need to be protected from the elements, so should be cleaned and examined closely at every opportunity – and in any event at least once a year. If damage to the paint coatings is discovered rectify by touching-up as soon as possible, before rust can get a grip. Also inspect wheels, especially rims, for bending or cracks caused by impacts with kerbs, etc.

Whenever tyres are removed from the rims, take a very close look at the well in which each tyre sits; moisture can be trapped and in the long run can wreak havoc with the steel. Wire wheels are especially prone to corrosion damage in this area, as the rim tapes (covering the ends of the spokes) can hold moisture against the steel. Check VERY carefully, for sometimes damage can be severe, yet still be hidden by the tape.

Aluminium wheels should also be checked regularly for corrosion and impact damage.

TIP OF THE WEEK PHOTO CAPTIONS

1. Surface rust on old wheel rims is not unusual, but if more deeply-rooted can spell disaster. At each service, make a point of closely inspecting each wheel while removed from your classic; check the insides too. If in any doubt, change the wheel(s).

2. On classics with wire wheels, potentially dangerous rust can fester unseen in areas normally covered by the tyres – especially beneath rim tapes. It is imperative to regularly and fully assess the true condition of each wheel.

Cylinder head gaskets are more likely to fail like this if the cooling system is in a bad way, and/or if the cylinder head is not torqued down correctly. Paying attention to both aspects can save an untimely breakdown and unnecessary expense.Tip 1: 

When a cylinder head gasket fails, it is always a nuisance and can be expensive to rectify. In addition, if the engine overheats there is the risk of it suffering severe and permanent damage. However, the chances of early failure can be minimised by attention to a few basics…

First, whenever a cylinder head is fitted, it is imperative that the gasket faces on both the head and the cylinder block are perfectly flat. A straightedge such as a steel rule can be used as a guide; when this is placed on the head or block face, it should sit uniformly flat against the metal, with no gaps between the two. If in any doubt, the faces should be examined and if necessary ‘skimmed’/re-faced flat by a competent engine specialist/engineering firm. Care should be taken to ensure that only the bare minimum amount of metal is removed, or the compression ratio will be unduly raised.

Whenever a cylinder head is installed, it is essential that the manufacturer’s recommended torque settings are strictly adhered to, also the sequence laid down for tightening the cylinder head retaining nuts/bolts.

ALWAYS follow the maker’s advice regarding checking/re-tightening the cylinder head fasteners after an initial period of running (typically, 500 miles). This is crucially important, especially if the cylinder head and/or block are made from aluminium.

Last, but not least, make sure that the cooling system is working effectively. A choked radiator or blocked waterways within the cylinder head and/or block will cause the engine to run too hot, as will a thermostat failing in the fully or partially closed position, or a defective fan. If the engine is permitted to overheat, the chances of head gasket failure, and more serious engine damage, will be far greater.

This fan belt looked fine from a casual glance, but close examination of the walls of the belt revealed that the main body of the belt was actually in two separate places. When did you check yours?Tip 2:

DRIVE BELT WOES

During a routine underbonnet examination of oil, coolant and fluid levels on one of my classics, I also took a look at the fan/dynamo/water pump drive belt, which initially appeared to be okay, but which on closer examination was found to be on the threshold of breakage!

The trouble is that the main ‘rubber’ body of a drive belt can crack all the way through to the outer backing ‘fabric’ which holds the belt together, yet from a casual glance it looks fine. This is because the outer part of the belt is usually the last part of it to fail, so a quick look tells you everything’s okay…

It can be difficult to see the true condition of a belt when in situ, due to inaccessibility and darkness in the area. The use of a torch or inspection lamp is helpful, and it’s wise to inspect the entire surface of the inner ‘V’ section of the belt. To do this it will be necessary to rotate the engine slowly by hand, so that you don’t miss a crack that may be hiding within the ‘V’ profile of a drive pulley. Needless to say, if a belt is found to be cracking (or even surface-crazed), it should be renewed at once. It’s always a good idea to keep a spare belt in the boot, as well, just in case…

An inexpensive plastic funnel like this one makes the task of topping-up engine oil much easier, especially if the neck of the filler tube is lower than the top of the motor (in which case using a full five litre can is just inviting spillage to occur…).

FUNNELLY ENOUGH

On many classics the engine oil filler tube is located in an inaccessible position, and/or the top of the filler neck is sited below the top level of the motor. In such circumstances, topping-up without spilling expensive oil can be difficult to avoid, especially if you are using a five litre container which is full, or nearly so.

One way to make life easier is to obtain a small can specifically for topping-up. Classic steel types, incorporating tapered spouts, are often found at autojumbles. Alternatively, an inexpensive plastic or metal funnel can be used. Such funnels can also be useful for topping-up some gearboxes and differentials.

Ideally, keep the filler can or funnel specifically for the one purpose, and always wipe it clean after use. Store it in clean conditions too, so that the surface cannot attract grit – and always check for cleanliness before using it again.

Courtesy lamps can fail to illuminate due to an accumulation of dirt or corrosion on the switch contacts, and/or poor earthing. Careful cleaning of all parts often restores operation. If the switch contacts have disintegrated like this one has; renew the switch! Tip 4:

NO COURTESY THESE DAYS?

An irritating fault, especially during the long dark winter days, is failure of a classic’s courtesy lamp to illuminate when one or both of the front doors are opened.

The manual override switch on door-operated interior lamps is a useful starting point to diagnosis any problems. If a lamp doesn’t work when the interior lamp is manually switched on or a door is opened, suspect either bulb failure or dirty/corroded bulb or switch connections. Check the bulb first by connecting it directly to a 12 volt supply and renew if it fails this simple test.

If the lamp illuminates when switched on manually but fails to respond to commands from one, or both, of the switches mounted in the door pillars, or if switching is erratic, it’s likely that one, or both, of the pillar switches is faulty. These are usually held in place by a single screw. These fixings can be difficult to shift if untouched for some time, so may require a good squirt of penetrating oil before being released.

Having removed the screw, GENTLY ease the switch and wiring a little way out of the pillar, to examine the cable(s), also the switch and its contacts. In many cases operation can be restored simply by cleaning up the electrical contacts (wiring to switch, and within the switch itself). However, if the switch is crumbling, or the return spring has rusted through, a replacement assembly will be required. If you cannot find an original switch, ‘universal’ types are often found at autojumbles or in motor accessory shops.

Believe it or not, this original, very old and brittle windscreen rubber seal provided invaluable clues to ensure that the new seal purchased had the correct profile, as fitted to the car when new. Don’t discard such items until you are sure you won’t need them. Tip 5:

DON’T THROW IT ALL AWAY

A reminder that during any restoration work, it’s always wise to keep all the old parts at least until correct replacements have been obtained. The originals may be worn out, but they still hold clues regarding construction and fitting requirements. In addition, in some cases it may be possible to have the original items refurbished. I’ve recently spoken to several enthusiasts who have regretted throwing away old components too soon!