DIY engine oil change. A quick guide to changing your own car engine oil.

The Engine Oil Bible

Doing it yourself: Changing your oil

Here is a generic, idiots-guide to changing the oil in your engine. It's not specific to any particular car but ought to cover most engines.

Before you start, you'll need the following :

  1. Start your engine and run it for a couple of minutes to get some heat into the oil
  2. Leave the engine to stand for 5 or 10 minutes. When you started it, it heated the oil but it also filled the oilways. You want the oil to drain back to the sump.
  3. Take the dipstick out or loosen it off and break the seal where it plugs into the engine dipstick tube. This prevents a vacuum building up behind the oil when you start to drain it.
  4. Get your drain pan / oil container and stuff it under the sump. Make sure it's sitting under the sump drain plug. I Really like the combined drainer / container types. They look like regular oil containers but if you lay them on their side, there's a pop-out plug. When you drain the oil, it runs into the side of the container, then you can put the plug back in and use the same container to take the oil away.
  5. Put your rubber gloves on. Try to use the disposable type. Your mum / wife will never forgive you if you use the washing-up gloves. Remember - used oil is toxic and carcinogenic. If you get it on your skin, it could cause problems. Use your socket wrench or allen wrench to loosen the sump plug just slightly. Once it's loose, remove it by hand.
  6. Be amazed as the black syrup runs out of the engine and into your container. Be more amazed how, if it's windy, those last dregs just won't hit the container no matter where you put it. They will however go all over the road/garage floor/cat.
  7. Remove the old crush washer from the sump plug and throw it away. Replace it with a new one. Use some of the oil from the drain container on the end of a rag to wipe around the drain hole in the sump. This will help clean any mess away and leave you with a smooth surface. Screw the sump plug back in by hand until it's finger tight and then use your wrench to crush the washer. This can vary from a quarter turn to a half turn. Don't overdo it or you'll strip the threads. Similarly, don't leave it too loose or it will fall out. If in doubt, use a torque wrench set to the value indicated in your shop manual.
  8. Now get your oil filter remover out. Push the oil drain container under the oil filter - when you spin it off, there will be a lot of oil comes out. Use the filter remover to grip the oil filter and spin it off anticlockwise. 99.9% of oil filters take some muscle to get going. This is why a filter remover is a must-have. Stabbing the filter with a screwdriver and using brute force may work, but you'll be finding oil all over yourself for weeks to come if you use that method. Apart from that, some cars have aluminium inserts that protrude out of the engine block into the body of the filter, so firing a screw driver into the filter near its base (the strongest part) may shear that aluminium bit off the engine block. That Would Be Bad. If you really can't lay hands on a filter wrench, try sandpaper - wrap it around the filter, sand-side-in and grip the paper backing - you might be able to spin the filter off like that.
    Once the filter is finger-loose, spin it off by hand. (these things below are filter removers)
    filter wrenches
  9. Clean off the face of the oil filter mount on the side of the engine block using a rag. Use a little oil on a rag to wipe around the seal of the new filter and spin it on by hand. Once it's locked against the side of the engine block, another quarter-turn by hand is normally enough to secure it in place.
  10. Pull the drain container out from under the car and use a rag to wipe down any excess oil that has spilled down the side of the engine block. Pay attention around the sump plug and the filter. These are places you'll be checking later for leaks so the cleaner they are now, the better.
  11. Use a little WD40 on the oil container and an old rag to clean the remaining oil down into the container. Put the plug back in and make sure it fits snug. That's your waste oil. Don't drink it.
  12. Up to the top of the again engine now. Put the dipstick back in. Find the oil filler cap and take it off. It might say "OIL" or it might say "710". It is not a "710 cap" as one person once asked for. "710" is "OIL" upside-down. Some people need to be told....
  13. Look in your shop manual for the system capacity with filter change. This will be more than the capacity without a filter change. A lot of oil containers now come with capacity marks on the side of them. Put your oil funnel into the oil filler hole and pour in the right amount of oil. Do it slowly. If you do it quick, you'll get airlocks and the funnel will burp oil in your face.
  14. Once you're happy you've got enough oil in there (check it with the dipstick if you're not sure), remove the funnel, replace the oil cap and replace the dipstick.
  15. Pull the main high tension wire from the distributor cap or in some way disable the engine so that you can crank it over but it WILL NOT start. (Note : you might want to pull out the fuel pump fuse too - if you crank the engine without it starting, it will still be pumping fuel - that could cause a backfire or damage the catalyst). Crank it over until the low pressure light goes off, and another 15-20 seconds for good measure. You are pumping new oil into the empty filter and then expelling all the air from the oil lines and cavities.
  16. Replace the high tension lead (and fuel pump fuse) and start the engine and let it idle for a minute or so. Stop the engine. I don't want you crawling under a car to look for leaks when the engine is running. There's so many things that can go wrong with spinning fan blades, belts, human hair, clothes, fingers and the odd dodgy auto-gearbox that will slip into "D" and run you over.
  17. With the engine off have a look at the side of the engine block around the oil filter. Check the area around the sump drain too. Both should be as clean as you left them with no sign of leaks. If there's a leak, a little tightening of the drain plug or filter should cure it.

One reader suggested and additional step before (9) above. When he changes his filter, he fills the new one up with clean oil and waits for it to soak into the filter itself. Once he's satisfied that the filter is soaked, he pours the excess oil out of the filter and then screws it on to the engine.

Job well done. Now you should have hands that smell of talcum powder and rubber (from the gloves), a couple of greasy, slippery tools and a container full of old oil. Oh, and a crush washer and filter. If you've got more than this, you took something off that I didn't tell you to. If you turned the engine off before checking for leaks, you should also have a full complement of fingers, hair (if you had it to start with) and you should still be fully clothed. Congratulations. You've changed your engine oil.

The Engine Oil Bible