Section A - General information

Keeping your vehicle on the road

One of Britain's fine cars

The 75 & ZT Enthusiasts group was formed with the aim of supporting Rover 75 and MG ZT owners, and helping to keep these fine cars on the road for the long term. If you would like to join 75 & ZT Enthusiasts, please register here. Once your registration has been completed, you will be able to use the forum, and also the other sections of the Wiki.

The Rover 75 and MG ZT are enjoyable, rewarding and reliable vehicles to own and to drive if properly maintained. The bodywork is not prone to corrosion, and most parts are readily available for everyday servicing and repairs. Vehicle diagnostic services are available from many firms around the UK, and also from some private individuals.

There is a good network of trade suppliers in place. This includes the worldwide parts distribution and servicing organisation supported by XPart Ltd and a number of other specialist companies. Some suppliers can also be contacted through the forum.

Meanwhile, if you are a new owner of a Rover 75 or MG ZT, you may like to look through the new owner's checklist set out below. Not all Rover 75 and MG ZT vehicles need attention to these items, but many do, so it is worth checking the ones that may apply to your car.

Further information about all of these topics is available through the 75&ZT forum, and in other areas of the 75&ZT Wiki.

New owner's checklist

These checks are in addition to the basic checks that you would carry out on any vehicle (covering such areas as lights, tyres, exhaust, coolant level, etc.). It is, of course, also a good idea to have a look at the vehicle handbook, and to purchase a workshop manual.

Bear in mind that the terms 'left hand side' and 'right hand side' are used when viewing the vehicle from the rear. Similarly, when referring to the engine, the crankshaft pulley end of the engine is referred to as the 'front' of the engine, and this is invariably on the right hand side of the vehicle. The direction of rotation of the engine is clockwise, when viewed from the front of the engine.

Vehicle identification

The vehicle identification number (VIN) is visible at the base of the windscreen on the left hand side, and around the top of the front suspension mount, under the bonnet on the right hand side. It should be the same as the VIN shown on the vehicle documentation. The last six digits of the VIN are the vehicle's unique serial number, and give an indication of when it was manufactured.

Bonnet catches

Check that the bonnet release cable moves freely, and that the catches are well lubricated and not too tight. The bonnet release cable divides into two separate cables at a divider block attached to the inner wing on the right hand side. If the release mechanism seizes up, perhaps due to lack of use, then one of the cables may break loose from the divider block. This can make it difficult to open the bonnet.

Plenum chamber

The plenum chamber is the space at the back of the engine compartment, directly below the windscreen. It is separated from the rest of the engine compartment by a bulkhead. Fresh air enters the plenum chamber through the plastic grilles at the base of the windscreen, and then passes through the cabin air filter into the passenger compartment. There are two drain tubes at the bottom of the plenum chamber - one on each side - to allow rain water to escape.

The engine computer is also located in this compartment, and is cooled by the movement of air passing through it. If the drain tubes become blocked (for example, by leaves or twigs) then water can collect in the plenum chamber and penetrate the vehicle's electrical system, giving rise to electrical faults. This is particularly the case with diesel engine models, as the engine computer is not sealed against water entry.

Handbrake

The handbrake mechanism includes a compensator, which is located under the carpet on the top of the transmission tunnel in the rear of the passenger compartment. The compensator is a metal link between the single cable attached to the handbrake lever, and the two cables leading to the rear brakes. It divides the force from the handbrake lever evenly between the two rear brakes.

Over time, the compensator stretches and becomes elongated, and the handbrake becomes progressively less effective. There is some adjustment available at the handbrake lever, but this may not be enough for satisfactory operation of the handbrake. The compensator may need to be replaced to keep the vehicle in a roadworthy condition.

Rear light seals (Saloon models only)

A thin foam seal is fitted between the rear light clusters and the metal of the bodywork. There is a joint in the seal which can open up, allowing water to enter the boot. This in turn can damage the electrical equipment in the boot. In particular, the radio and video modules for the Highline navigation system are located in the spare wheel well under the boot floor panel, and can be damaged by water entry. Replacement seals are available.

Cooling fan

There are several different control system designs for the radiator cooling fan on the different models of the Rover 75 and MG ZT, but they all use the same fan, and a very similar motor assembly. Depending upon the design of the control system, the motor brushes may wear out, or the speed control series resistor may fail. In either case, this may cause the cooling fan not to run when the engine becomes hot. It is usually the 'low speed' setting of the cooling fan which fails.

Whilst this may not be too serious for the diesel engine models, which tend to run very cool, it is more serious for the V6 engines, and in particular for the 1.8 K Series engines. This is because the 1.8 K Series engine has a relatively small coolant capacity (about 6 litres, compared with 7.5 or 8 litres for the other engine types) and is therefore very sensitive to any problems in the operation of the cooling system, and can quickly overheat as a result.

It is also detrimental to the air conditioning system. This is because the air conditioning compressor is designed to be cooled by a flow of air whenever it is operational, and the low speed fan setting is provided for this purpose. If the low speed setting has failed, the air conditioning system may not work correctly.

Coolant level checks - 1.8 K Series engine

Due to the small reserve of coolant in the 1.8 K Series engine, the coolant level should be checked regularly. Overheating of the engine can contribute to distortion of the inlet manifold, loss of coolant, and ultimately head gasket failure.

Thermostat housing - V6 engine

The thermostat housing on all KV6 engines is located in the 'vee', below the engine cover. It is made of a form of industrial plastic, and can become brittle over time. This can give rise to coolant leakage, which can be seen as a pinkish deposit collecting within the vee of the engine. In extreme cases, the thermostat housing may disintegrate, leading to loss of coolant. Whilst the KV6 engine usually survives without serious damage, it is not improved by the experience. Regular checks will allow any early signs of leakage to be corrected.

EGR valve and PCV filter - Diesel engine

In order to comply with emission requirements, the diesel engine is fitted with an Exhaust Gas Recirculation (EGR) valve, as well as Positive Crankcase Ventilation (PCV). The EGR valve feeds exhaust gases back into the inlet manifold under certain engine conditions, whilst the PCV valve allows crankcase gases also to return to the inlet manifold. Opening and closing of the EGR valve is controlled by the engine computer, whereas the PCV valve is a simple passive device.

Over time, the EGR valve may become partly clogged by combustion deposits, and may need to be cleaned. This may be more likely if the vehicle has been used at low throttle openings and on many short trips. Similarly, the PCV valve is equipped with a filter, which may also need to be cleaned or replaced. These operations are not normally part of the manufacturer's recommended service procedures, and may not have been carried out over the life of the vehicle.

Road springs

The front and rear coil suspension springs can occasionally break in normal use. This may be due to a combination of more highly stressed modern materials, poorer quality road surfaces, and possibly surface corrosion of the road springs. Failure of a front road spring can seriously damage a front tyre, leading to almost immediate loss of tyre pressure. A 'tyre protector' kit was issued by the manufacturer in April 2004 (applicable to VIN serial numbers from 133300 to 247257).

Experience has shown that the tyre protector kit is not always effective in preventing tyre damage. On the other hand, a broken front road spring may cause no damage to the tyre, and may go undetected for a prolonged period of time. Owners should therefore keep an eye on the vehicle ride height, and occasionally carry out a visual check on all four road springs, including a check for possible surface corrosion of the spring itself.