An engineer checked out my week 22 (27/05/14) built Yeti and confirmed it has a chain driven cam.

It must be chain if the cover is aluminium as opposed to a 'ventilated' (non-sealed) plastic one.

The cover was black plastic.

The cover was black plastic.

So I wonder how they seal the oil in.

Yes, but they can do wonders with plaskit these days...I am though going to investigate this further. I took it their expert would/should know.

To me at least, it would be a first.

If you look at this video,

 

http://www.youtube.com/watch?v=PY91c8JCwv0

 

The chain cover is in two pieces so I was looking at the top...the black plastic.

So I wonder how they seal the oil in.

The cover over the oil filter element is plastic....that seems to do a good job of sealing oil in

Skoda UK CS say it is a chain.

You can see a cam belt, you can't see a chain.

Never seen or heard of a plastic chain cover.

To me it's a first if true.

The oil filter top is threaded and has a rubber "O" ring seal, so not flat surfaces as the timing chain cover would be.

If you look at this video,

 

http://www.youtube.com/watch?v=PY91c8JCwv0

 

The chain cover is in two pieces so I was looking at the top...the black plastic.

Great video.

I thought VW had an issue with the chain stretching which they resolved with a belt.

I thought all their engines were belt driven cams.