Checking Oil Consumption
Checking oil consumption
Normal oil consumption
During a running-in period of approx. 5,000 km for new or reconditioned engines (piston ring replacement), up to 1 litre of oil per 1,000 km can be consumed.
After the running in period, with a mixture of free way and town driving, up to 0.4 liters per 1,000 km is considered normal.
The above oil consumption figures can be used as a guide if oil consumption seems abnormally high. In order to determine the exact oil consumption, a controlled test drive of at least 1,000 km has to be carried out. The oil should be weighed before and after the test distance is driven in order to determine the exact oil consumption. See also.
Continue - Checking for abnormally high oil consumption
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Checking for abnormally high oil consumption
If a customer complains that the oil consumption is abnormally high, a few basic checks should be carried out first before taking further action such as a test drive or carrying out any work on the engine.
- Ask the customer questions about the driving conditions.
- Check if there is any oil leakages.
- Check that the crankcase ventilation is not blocked.
- Check that the correct dipstick is being used in the engine. The dipstick must be pushed fully home in order for the correct oil volume reading to be given.
- When checking the oil, place the car on a non-sloping surface. The engine should be driven until it reaches the normal operating temperature, then wait for 15 minutes after switching off the engine before checking the oil.
- Remove the intake manifold.
- Check to see whether there is a film of oil droplets of oil in the cylinder head intake passage and/or oil on the upper side of the valve stem/valve crown.
Are there abnormal traces of oil on the intake passage and the valves?
Yes - Oil consumption has always been high
No - Gradually increasing oil consumption
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Oil consumption has always been high
Oil consumption is above 0.80 liters/1,000km.
The problem is probably in the cylinder head.
- Check for another fault in the crankcase ventilation other than blockage.
Was there any other fault in the crankcase ventilation?
Yes - FAULT FOUND
No - Checking valve stem seals
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Checking valve stem seals
If traces of oil are found on the valve crown, in the ducts or on the valve stem, the valve stem seals should be changed.
Is there any oil?
Yes - Replacement of component
No - Checking cylinder head
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Replacement of component
Replace valve stem seals.
Continue - FAULT FOUND
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Checking cylinder head
Carefully examine the cylinder head to see if there is any internal leakage. If traces of oil are found and defects in the cylinder head are discovered, the cylinder head should be replaced.
Is there any internal leakage?
Yes - Replacement of component
No - Replacement of component
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Replacement of component
Replace cylinder head.
Continue - FAULT FOUND
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Replacement of component
The engine should be replaced if the problem cannot be solved otherwise.
Continue - FAULT FOUND
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Gradually increasing oil consumption
- Oil consumption, previously acceptable, has gradually started to increase rapidly.
- Oil consumption lies between 0.30-0.80 liters/1,000 km.
- Replace piston rings.
Continue - Checking engine block
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Checking engine block
If damage is discovered in the cylinder block (worn cylinder bore, deep score marks etc.), this should be replaced, along with the pistons and piston rings.
Is there any damage in the cylinder block?
Yes - Replacement of component
No - Checking valve stem seals
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Replacement of component
Replace engine block, pistons and piston rings.
Continue - FAULT FOUND
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