TD5 noise

Ive just picked up a new TD5 90, after ive been out for a run and switch it off there is a whining noise from the engine area. Is this normal? What is it? Is it the turbo slowing down? Any input would be appreciated.
Cheers Steve.

Does it have an electric fan?

that's the air filter spinning down. it's normal.
it's spins abt 10000 rpm so when you cut the engine, you can hear it spin down. if you hold the gear shift you can also feel it.

Hi Steve, just to clarify a little more, the TD5 engine has two oil filters, a conventional one and a centrifugal one, which the last guy was referring to. If you look under the bonnet, it's on the right side of the engine, a few inches below the top and in the middle, roughly, and a little hidden. It's about 4" in diameter. It has 3 x 10mm bolts holding the top on. Inside there's a very small dome shaped filter which whizzes round at great speed and being well lubricated, it carries on after the engine stops. When you get around to your own servicing in 3 years, it'll be a job to do. The top is sealed with a large 'O' ring.
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