The objective of this procedure is to show you how to check and adjust engine oil level and condition. Make sure the vehicle is on a level surface and the engine is off before taking a reading. If you don't, you'll get inaccurate readings.
Part 1. Preparation and safety
- Check and adjust engine oil level and condition.
Whenever you perform a task in the workshop you must use personal protective clothing and equipment that is appropriate for the task and which conforms to your local safety regulations and policies. Among other items, this may include:
- Work clothing - such as coveralls and steel-capped footwear
- Eye protection - such as safety glasses and face masks
- Ear protection - such as earmuffs and earplugs
- Hand protection - such as rubber gloves and barrier cream
- Respiratory equipment - such as face masks and valved respirators
If you are not certain what is appropriate or required, ask your supervisor.
- If the engine has been running, be careful not to burn your hand or arm on the exhaust manifold or any other hot part of the engine when reaching for the dipstick. Remember, the dipstick and the oil on it will also be hot.
- Dripping oil from the dipstick will smoke or burn if it falls on any hot engine areas.
- Make sure that the hood is secure with a hood stay rod.
- Always make sure that you wear the appropriate personal protection equipment before starting the job. It is very easy to hurt yourself even when the most exhaustive protection measures are taken.
- Always make sure that your work area/environment is as safe as you can make it. Do not use damaged, broken or worn out workshop equipment.
- Always follow any manufacturer's personal safety instructions to prevent damage to the vehicle you are working on.
- Make sure that you understand and observe all legislative and personal safety procedures when carrying out the following tasks. If you are unsure of what these are, ask your supervisor.
Points to note
- Make sure the vehicle is on a level surface and the engine is off before taking a reading. If you don't, you'll get inaccurate readings. The oil will also collect in the sump when the engine is off.
- Typically, the amount of oil needed to raise the oil level from the low mark on the dipstick to the high mark is about a liter. This varies, so always check the shop manual to determine the correct quantity. Never fill the engine with oil to the top of the filler cap!
- Although fresh oil is translucent, and oil that needs to be replaced looks black and dirty, it is often difficult to assess the condition of engine oil simply by its color. Oil loses its clean, fresh look very quickly and yet may still be serviceable. The best guide to changing oil is knowing the vehicle's mileage and period of time since the last oil change.
- If the oil on the dipstick is not blackish in color but looks milky grey, this could indicate that there is some water (or coolant) being mixed into the oil. There may be a serious problem somewhere in the engine, such as a leaking head gasket, and you should report this to your supervisor immediately.
- Engine operating conditions can also influence the oils condition. For instance, continuously stopping and starting the engine with very small operating cycles can cause condensation inside the engine. An extreme case of this will cause very rapid oil deterioration, and will require frequent oil changes.
- Don't forget to replace the filler cap after topping up the oil.
Part 2: Step-by-step instruction
- Locate dipstick
The dipstick is located on the side of the engine block and is usually very easy to find, with a distinctively shaped or brightly colored handle.
- Remove dipstick and wipe clean
Remove the dipstick, catching any drops of oil on a rag, and wipe it clean. There are markings on the lower end of the stick to indicate whether the oil level needs to be topped up.
- Take the oil level reading
Replace the dipstick and push it back down into the sump as far as it will go. Remove it again, and the level of oil in the oil pan will be clearly visible on the stick. If the level is below the ‘full’ or topmost mark, then you should top up the engine to that level with fresh oil.
- Check condition of oil
If the oil appears very black and dirty, it may have lost some of its protective and lubricating qualities and may need to be completely changed. Check the service record or ask the customer when the oil was last changed.
- Adjust level if necessary
If additional oil is needed, estimate the amount by checking the service manual guide to the dipstick markings. Unscrew the filler cap at the top of the engine, and using a funnel to avoid spillage, gently pour the oil into the engine.
- Recheck the dipstick level
Replace the oil filler cap, and check the dipstick again to make sure the level of oil in the engine is now correct.