850 T-5R L5-2.3L Turbo VIN 58 B5234T5 (1995)
Engine Oil: Technical Service Bulletins
Engine - Oil Consumption
GROUP:
22
No:
108
Date: 1/93
Oil Consumption
850
This bulletin describes procedures to identify abnormal oil consumption.
GENERAL
It is normal for a certain quantity of oil to be consumed when an engine is operating. The actual quantity varies considerably and depends on a number of
factors:
- Engine condition - state of tune, maintenance
- Driving conditions - heavy load, frequent idling
- Oil quality and viscosity
- Cylinder displacement - in general, larger engines use more oil than smaller engines
- Engine power - a more powerful engine usually uses more oil than a less powerful engine
- Number of valves - in general, engines with multiple valves consume more oil than engines with fewer valves
- Oil level - overfilling leads to higher oil consumption
ASSESSMENT OF OIL CONSUMPTION
Oil consumption is normally measured in quarts of oil per 1,000 miles or liters per 1,000 kms. If a car is operated under conditions where there is
frequent engine idling, this must be taken into consideration when making the assessment.
During the running-in period, approximately 3,000 miles or 5,000 kms for a new or reconditioned engine, higher oil consumption is to be expected. This
figure is about 1.6 quarts per 1,000 miles or 1 litre per 1,000 kms.
After the running in period the oil consumption at mixed urban and highway driving should normally not exceed 0.7 quart per 1,000 miles (0.4 liters
/1000 kms)
To use the above oil consumption figure as the limit for further evaluation, it is necessary to carry out an oil consumption test where by the oil is weighed
before and after the test to determine an abnormal condition. A minimum of 600 miles or 1,000 kms must be covered during the test.
ABNORMALLY HIGH OIL CONSUMPTION
Always begin by checking and rectifying any oil leaks. Also check that the crankcase ventilation is not clogged.
Ensure that the engine is equipped with the correct oil dipstick. It is essential that the correct dipstick is used and that the dipstick is inserted all the way
into the duct during measurement, otherwise the reading will be incorrect.
Park the car on a level surface. When measuring the oil level in a warm engine, it is important to remember that the engine must be switched off for 5 -
10 minutes before the oil level is measured. This is done in order to give the oil sufficient time to flow back down to the sump, thus allowing sufficient
time for stabilization of the oil level. Note also that waiting longer than 10 minutes allows the oil to cool, which causes a reduction in its volume.
When topping up the engine, note that it takes a long time for the oil to run all the way down to the sump, which is why the oil level should NOT be
measured immediately after topping up.
Never add more oil than the quantity recommended in the applicable car owner's manual. Also see under REASONS FOR HIGH OIL CONSUMPTION.
REASONS FOR HIGH OIL CONSUMPTION
INCORRECT MAINTENANCE
Over-filling:
If the oil level is too high, an excessive amount of oil will be thrown up against the cylinder walls. The oil level should be kept at or a little under the
