Unfortunately it is true, the Freelander 1.8 petrol is prone to head gasket failure. In fact, this is a common issue for all cars that use the Rover K series engine. Why?
The original head gasket fitted to the Freelander 1.8 petrol model was a single layer gasket that proved a bit too flimsy for the job in hand - unfortunately they usually blow by about 75,000 miles. Since then a modified multi layer head gasket has been developed which is much more robust, and you should insist on one of these being used for any head gasket change as it protects the head cylinder from cracking and damage if the head gasket blows.
However this does not answer the question as to why the head gasket fails. The engine block and cylinder head are aluminum. Oil and water (with coolant) flow through channels here and if they lose their viscosity then it causes the engine to run at a higher temperature than normal, which puts pressure on the head gasket and can cause it to blow.
There are four main reasons why a head gasket blows:
1. Insufficient water;
2. Deterioration of antifreeze efficiency;
3. Deterioration of oil;
4. Failure of the thermostat.
Looking at each of these in turn will help us to understand what to look out for as warning signs and what we can do to avoid a head gasket failure.
1. Insufficient Water
Insufficient water in the system can be cause by a number of things:
a. Not topping up the water as general maintenance;
b. A leak from the water pump (which will be seen as water leaking from the front drivers side of the engine);
c. A leak in one or more of the coolant system hoses;
d. Water reservoir bottle pressurising, causing water to leak from the cap;
e. A deteriorated head gasket allowing water to leak into the oil. If this happens you will see a creamy mix of oil and water in the oil tank and/or possibly some sludge in the water reservoir bottle.
Although you cannot avoid all of these causes, making sure that you check the water bottle regularly, preferably every week, will give you an indication of whether your Freelander is using more water than normal. If it is - STOP DRIVING IT UNTIL YOU HAVE IT CHECKED OUT BY A PROFESSIONAL. Continuing to drive your Freelander when it is losing excessive water could cause a lot more damage than is necessary.
2. Deterioration of Antifreeze Efficiency
The Land Rover Freelander uses a red antifreeze. Models up to June 2000 use antifreeze to specification BS 6580 and BS 5117 which is ethylene-glycol based with non-phosphate corrosion inhibitors, containing no methanol. The mixture should be 50% by volume. Models from 2000 onwards use ethylene-glycol based antifreeze, containing no methanol with only Organic Acid Technology (OAT) corrosion inhibitors.
It is important that you use only the recommended antifreeze in your Freelander, and always top up with an antifreeze mix and not plain water. Make sure that you renew the antifreeze every 36,000 miles.
3. Deterioration of Oil
As the oil in your Freelander gets older it thickens and picks up dirt. This means that it does not circulate in the system in the same way as fresh oil and can cause the temperature to rise, hence blowing the head gasket.
Make sure that you check your oil levels regularly, preferably every week, and that you have the engine oil replaced at every 12,000 mile service.
4. Failure of the thermostat
This is the most difficult fault to preempt. If the thermostat fails the temperature of the engine will increase and hence cause the head gasket to blow. A sign of a failed thermostat is the fan not cutting in - however this could also be a sign of other faults and may not be the thermostat.
Hence, in order to have the best chance of avoiding a head gasket blow on your Freelander you should:
(i) Have a routine change of the head gasket to a modified multi-layer gasket by 75,000 miles - this will be much cheaper than sorting it out after it has blown.
(ii) Check your water level weekly and note any unusually high usage or oil residue in the water reservoir.
(iii) Always use the recommended antifreeze in with the water and top up the water reservoir when required.
(iv) Check your oil level weekly and watch for any mixing of water with the oil.
(v) Have your oil changed at every 12,000 mile service.
(vi) Keep an eye on your temperature gauge and note if it is running hotter than normal (it should generally sit around the half way mark when the engine has heated up).
It is paramount to STOP DRIVING your Freelander if it is:
- overheating;
- losing an abnormal amount of water;
- mixing oil and water.
If you continue to drive your Freelander you run the risk of cracking the head cylinder or damaging the cylinder block liners - which will mean that on top of the cost of replacing the head gasket you will also have to buy a new cylinder head!
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