Check your fan belt

Posted by Jon May 30, 2012

Did you know the fan belt on an air-cooled engine has a specific tightness? Too tight or too loose and you could be in trouble.

One of our pet hates with technical features is statements like ‘check this or that and adjust if necessary.’ Great if you know what the adjustment should be, but no use whatsoever if you don’t. The reason of course is that a lot of jobs on cars require a certain amount of ‘feel’, but this feel only comes with knowledge and experience, and can put a first timer off from doing what’s otherwise a simple job.

The fan belt on your Beetle is a vital piece of kit and one that you should check regularly – and not just when the red generator light comes on on the dash! It not only keeps all your electrics working to the best of their abilities by spinning the dynamo (or alternator), the clever design of the Beetle engine means it also spins the fan that supplies vital cooling air to your engine. If it’s not working properly neither of these important jobs will be done right, which is bad news.
So first off, open the engine lid and have a look at your fan belt. Grasp both sides of it between the pulleys in your hand and give it a squeeze – not while the engine is running though, eh? How does it feel? Loose as a whore’s drawers or a tight as a duck’s butt?
See if you can turn the engine with it by pulling down on one side and up on the other, or does it slip on either of the pulleys? Give it a twist and check it for cracks, frays or to see if it looks shiny. Any of these things and it needs replacing. It doesn’t matter what type you replace it with as long as it’s the correct overall size and width.
You don’t necessarily have to be quite as precise as we’ve been here because this is just to show you how much deflection you should expect from your fan belt but there’s no harm in doing the job properly. You don’t have to apply excessive pressure to test deflection, just sturdy finger pressure is fine.

Feel free to download this article as a .pdf file so you can print it out and use it in your garage. However we do recommend reading the entire article first, so you can familiarise yourself with the procedure and know what your getting in to.
(To save the file to your computer right click the link below and select ‘Save file as’ or ‘Save linked file as’. If you click the link normally it will open in your browser.)