the guides are probably knackered. I've done 119,000 and mine sounds like a back of bolts even with a Ballards TCT. Get the chain and guides replaced when you can... I wouldn't worry about it too much though as the likely hood of the chain actually breaking is next to none but get it replaced when you can.

I think the last quote i got for chain and guide replacement was around £700

 

I've just dropped the car off at TGM to having the sump taken off and the bearings inspected. I've also asked Tom to do a compression test if he cant find any wear on the rod bearings.

The car is still driving well apart from the terrible rattle when the revs are held at ~2.5-3k rpm. If the rod bearings aren't the issue, apart from the main bearings I'm not sure what else it might be. I don't really want to open the engine up to check the main bearings, especially if no swarf is found in the sump. I might just have to live with it if the source of the problem isn't found today.

To the last poster: it sounds like the noise is stronger in the timing chain area, though the timing chain, guides and sprockets were all replaced by the previous owner 5k miles ago, so it probably isn't that.

 

It doesn't sound like rod knock, at least not from the video sound. Did you think to have an oil presure check done?

 

Gunna put this out there as a shot in the dark, checked the clutch and gearbox?

 

That will probably be the next route of exploration. The noise does seem to amplify as soon as clutch the engages at the bad rpm zone, though this may be from the rpms being held for longer than normal as the clutch engages.

The rod bearings were fine, no damage or wear on them. The oil sump was also remarkably clean. Hopefully that means this is not an engine internal issue.

 

This is a noise that many people (more so on the US forums) have failed to diagnose, your noise is admittedly louder than some others. Some Americans have spent a fortune in trying and failing to get rid of this noise, my car makes it very occasionly although not as loud as yours (cold and warm). I realised that the tempo of the noise can change when the clutch is depressed.

I took my clutch slave cylinder off and greased the pivot in the clutch fork, hey presto the noise was gone

The pivot pin/bar in the clutch fork can work loose over time and make a noise like this, please bear in mind this is my theory only.
the faint noise has started to come back slightly which is inline with the grease dispersing causing the pivot to rattle again. If I ever take the box off I will change the fork, in the mean time I wont worry about it.

Have a look at this https://www.youtube.com/watch?v=2GkWdHfFkjk

 

It may well be the clutch fork. Does yours sound anything like this? I can here my rattle when the clutch is in or out, though the clutch does momentarily change the tempo when you release it as you change gear.

https://youtu.be/D4tKyMcupcc

 

I have had a listen at work just now, and struggled to hear anything conclusive TBH, when my car makes the noise it is only at idle, when revving it goes away.

not a great help to be honest, although there is nothing there that would alarm me.

 

Have you checked the water pump? I know it sounds bizarre but I thought my engine had piston slap or big ends going but when I started to look I found it to be water pump. Although it's not the same sound it's easy to check, just take off the aux belt and give the water pump a wiggle. I'm not saying it is this but it's possible. I went to a meet on Thursday in Malpas and couple of the guys noticed it there (because I still not changed). Just a idea that's all

 

I haven't yet no. I will get the stethoscope out for now. I've just moved house and have no tools so cannot take the aux belt off just yet. It really sounds like its the engine internals making the noise, specifically somewhere in the head.