VW air-cooled oil service tips

If you’re about to hit the road again in your classic air-cooled VW, it’s wise to treat it to a proper once over first. To kick things off, here’s our easy-to-follow guide on how to carry out a basic air-cooled engine oil change and gearbox service…

The beauty with old Beetles, Buses and other air-cooled VWs is their simplicity – and the fact that carrying out an engine oil change service yourself is actually a lot easier than you might think. Yes, you’ll need some basic tools and some space in which to work – but for very little financial outlay even the most novice home mechanic will have the job done in no time…

Because Volkswagen’s air-cooled engine relies on its oil for cooling as well as lubrication, replenishing it religiously every 3000 miles is crucial. There’s no harm doing it a little sooner if a car’s been left standing for a long time or if you do a very low annual mileage.

To help ensure all the old oil drains efficiently, warm the engine first by taking a quick spin around the block. Then, with the vehicle parked on level ground (not on axle stands), begin by climbing underneath with a suitable container and place it under the sump plate – it will need to be big enough to contain 2.5-litres of oil.

The sump plate itself may have a central 19mm sump plug, if so undo it. Otherwise, it will be a case of partially undoing the six 10mm acorn nuts that hold the sump plate in place and letting the old oil slowly drain out. When it’s stopped dripping, remove the plate completely, being careful not to lose any of the nuts in the murky old oil you’ve just drained. When you’ve done that, carefully prise off the alloy oil strainer. A two-part paper gasket is sandwiched between the filter, the bottom of the engine and the sump plate so remove that too. Transfer the old oil into an old container of oil and dispose of it at your local recycling point.

With everything off, give the metal strainer and sump plate a thorough wash in petrol or degreasing fluid, being careful to wear the appropriate protective gloves.

The new oil change kit (below) will come with two circular paper gaskets and copper crush washers for the acorn nuts and the central sump plug if you have one. So, once everything is clean, put it all back in place – with the paper gasket either side of the strainer – and carefully tighten up the acorn nuts. Never use gasket sealant – it’s not needed. Don’t over tighten the nuts, they only torque up to 5lb ft, so there’s a danger that you’ll sheer them off.

Now it’s simply a case of filling your engine with lovely fresh new oil. We recommend Morris Oils’ SAE 30 mineral oil – and, as we said earlier, it takes 2.5-litres. Don’t put too much in and be sure to check the level on the dipstick to get it spot on. Start the engine and check underneath for any oil seepage from sump plate – if you spot any drips be prepared to give the bolts a careful tweak to tighten them up a bit.

Finally, before hitting the road – why not add that extra piece of mind by checking the gearbox fluid. You’ll need a special 17mm Allen key with a socket fitting to undo the plug, then poke your finger in to see if you can determine the level. If necessary, top it up with hypoid EP80/90 gearbox oil via a flexible pipe. If you want to go the whole hog and replace all the fluid, drain the gearbox in the same way as you would the engine and refill with 2.5-litres of fresh fluid.

Happy servicing!


The opinions expressed here are the personal opinions of the author and do not necessarily represent the views and opinions of VW Heritage


This post is also available in: Deutsch (German)

8 responses to: VW air-cooled oil service tips

  1. Hi, some advice please, beetle motor 1972. Removed the oil strainer to clean. The metal pipe that it connects over in the casing referred to as “”oil suction pipe” in the manual is loose and I am battling to seat it correctly so that I can fit the oil strainer again. How does it connect inside the case as I can’t see the inner connections?

  2. Have a t2 bay automatic, slight leak on gearbox but when I check the dipstick it shows full, but gears slip in 1st when warm, is it low oil or needs new clutch?

  3. Hi ,I have baught 1969 BEETLE classic and from 1st to 2nd sometime a crunch ,tried all adjustments,,or from 1st quick wiggle and 2nd ,with a bit of practice,,any idea ,have changed bushes and selection plates, tried reverse fitting as well, same problem

  4. Problem with 1st to 2nd, done the bushings ,new plate, changed it round, bit of wriggle then its fine ,also problem with headlights flasher, changed relay ,remade all Earth connections,,,rebuilt engine 1500,AB block ,on cold start slight noise in tapets ,then runs smoothly,,do I use a 5,30 oil have just changed oil 30 ,50 ,,,any help appreciated

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