1994 940GL wagon, B230FB (non turbo) 2.3L motor, 171,000km

I do my own oil changes and monitor the oil level regularly, checking the dipstick each time I fill the car up with petrol. The oil level drops slowly and steadily over time. I use a dino oil (Castrol Magnatec) and have a totally drip tight motor as regards oil leaks.

It took 5200kms for the oil to go from the full to the low mark on the dipstick after the most recent oil change. I'm not sure what volume of oil this represents as I never top up the oil - when it gets to the low mark I just change the oil and filter. Is this an OK rate of oil consumption ?

I'm not aware of the car blowing any oil smoke out the exhaust. After driving around, stopping the motor and removing the oil filler cap I have noticed that it is a bit fumey in the top of the cylinder head, but nothing excessive. At what rate should a "perfect" motor consume oil at ? Is some degree of cylinder head fuming after turning off the motor normal ?

I wonder if I should I top up the oil and go a bit longer as regards oil and filter changes ? (I do about 15,000 km per year, mostly around town, so do 2-3 oil changes a year under my current method, which does strike me as a bit excessive perhaps.)


John Marshall
Christchurch NZ