MG Tech – Oil Change

Something that most owners can do is an oil change – here’s Roger Taylor’s  step-by-step guide.

Draining the oil from the sump is easier if you can raise the car to a convenient working height on something like a post lift – but if you only have axle stands remember to check that they are secure and on firm ground.

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Carefully remove the sump nut and ensure you have a container in place to catch the waste oil – typically an MGB holds seven pints of oil so it needs to be quite large to take it all.

When empty, replace the sump nut and use a new copper washer as these can deteriorate over time.

While the car is raised this is an opportunity to also check the gearbox drain nut and the oil level in the rear differential – never over-fill and examine the drain nut (which will be either hexagonal or square) for tightness. At the same time check the breather on the rear axle for signs of corrosion.

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Next move on to the oil filer holder – while underneath, check that the securing nut is tight in position.

Before unscrewing the oil filter place a tray underneath to catch any excess oil that may run out. The filter should only be hand tight but, if it does not move, you will need a special grab tool to hold it while you unscrew.

Fit a new filter and ensure it has a seal with it – hand  tighten it in place.

When it comes to replacing the oil, Roger recommends using 20/50 Castrol Classic or a Unipart mineral based oil rather than modern synthetic oils which can harm older engines.

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Roger advises to always measure accurately the seven pints of oil you put in as it is not unknown for cars to have the wrong dipstick which can give you a false reading.

Before dropping the car to the ground, check all-round for signs of any leaks.

Finally check the gearbox oil level – on the MGB this is located under the carpets on the transmission tunnel just below the dashboard and can be fiddly to access and check. You will need a long tube to top-up the gearbox using the same 20/50 oil.

Remember to dispose of the old oil and filter in a safe and environmentally friendly manner – these can be taken to civic amenity and recycling locations.