TDCi DW10 Engines: Cam Chain Oil Supply

[AlCan]

Hi Guys,

A while back AlanM and I touched on the reliability of the inter-cam timing chain when subjected to poor maintenance. Apparently, if (oil changes are) neglected, it is prone to early severe wear, perhaps in some (2.0?) TDCi engine variants more than others. Now I'm wondering, why the chain, in particular?

Can anyone comment on this, please?

I recently bought a 2013 MC Wagon (TXBB? / DW10C engine), 133,000km.

The first time I started it after buying it - after it had been sitting for a while - I noticed that the cam chain was quite noisy. I noticed this again the next time also, when I was showing it to a friend and just figured, we've got a worn chain.

However, this time, while we were standing chatting in front of the idling engine - bonnet open with "beauty cover" off - I noticed that the chain was suddenly becoming quieter. It continued becoming quieter and quieter until it was barely noticeable. This took maybe half a minute - after already running for a minute or two.

Clearly, it was suffering from either lack of lubrication, or lack of tension - or both. Based on this observation, the oil flow to either the chain or (maybe?) the tensioner is very limited - maybe almost blocked?

My question for AlanM or anyone who might know: what does the Oil Supply to the cam chain consist of? Is it a small-orifice jet or spray, or is it merely splash from some other source? What's the chain tensioner situation - is it oil pressure driven? I suspect from watching an Alan Howat video that it is, but I don't think it was confirmed in the video.

The next question: what would it take to clean / fix it?

Any suggestions, please?