Whenever you change the oil on your car you also need to change the oil filter. It's a straightforward job, but you do need to follow some simple rules. Read on to find out more…
Where is the oil filter located?
The oil filter's location varies from car to car. It's often accessible only from underneath, and may be shielded by the undertray which will need to be removed first. On some cars the filter can be accessed from above. Check your handbook for the exact location if you're unsure.
Types of oil filter
Oil filters generally come in two types, screw-on metal canisters, or replaceable paper elements that fit within a cylindrical plastic housing. Both perform the same function and operate the same way.
How to remove the oil filter
Screw-on oil filters should only ever be fitted hand-tight, but not everyone heeds this advice. In most instances it should unscrew with a firm hand.
The housings for paper oil filter elements have a cap that unscrews. Once open the paper element simply lifts out – be aware that with both filters a fair amount of oil may come out when you loosen them.
How to remove an oil filter cap
Oil filter housings pretty much always have a screw-threaded cap and are removable with a socket. It's often a very large socket (sometimes up to 36mm).
You can buy model-specific housing sockets so check what you need before you start draining the oil!
The worst case scenario would involve the housing cracking, either from the cap being applied too tightly, or from age related fatigue. Luckily replacement housings are available, and aren't too challenging to fit.
How to remove a stuck oil filter
If you have a screw-on metal oil filter and it's not budging you have a couple of options. Before you try anything destructive clean the filter of any oil or dirt and put on some latex or rubber gloves.
Manoeuvre yourself into the best position to be able to apply force to the filter, make sure you're twisting anti-clockwise, take a deep breath and go for it. In most instances this will work – if not you need to get an oil filter wrench.
These have metal, or rubber straps that allow you to apply extra leverage to the filter. If there's access you can also attempt to unscrew the filter with a large pair of water pump piers.
Finally, if you're desperate to get it off you can drive a large screwdriver into the side of the filter and use the extra leverage to free it – but be warned, if this still doesn't work you can find yourself stuck with a ripped open filter, jagged metal, and a car that won't work, so it really is a last resort!
How to install a new oil filter
Once the oil is drained and the old filter removed you'll need to fit the new filter. For a screw-on filter make sure the mating surface on the engine is clean and free from dirt, and smear some clean oil onto the rubber seal around the rim of the filter.
Now – taking care not to cross thread it – screw the filter on. Once you feel it making contact with the mating surface tighten a further quarter turn – only ever tighten it by hand.
For paper element filters, pop in the filter, and lightly oil the rubber seal (that should be supplied with the filter element), replace the seal and cap (again taking care not to cross-thread it) and tighten.
Once again you only need to nip it up till it bites. With both filters keep an eye on them over the next few days, and if they show any signs of leaking tighten no more than a quarter of a turn until they're leak free.