XC90 mk2 D5 bearing failure

[anthv50]

Originally Posted by Kev0607

That’s fair enough.

The alternator clutch pulley can make a bit of a racket when they start to wear, so can a water pump. I wouldn’t expect the water pump on such a new car though, but you never know.

I've fitted a new aux belt and tensioner today, genuine parts direct from volvo, wallet £152 lighter and no fix. I've got it booked in a local garage for next week who suggested I did this first before they started buying parts to change to work out what it is. I'm 99% sure it's something ran by that belt, but it's beyond me to diagnose it further.

I'm going to spend the next few days finding as many part numbers and part availability. Getting information on this engine has been quite difficult. Most stuff online is from America where the petrols are the main models, but here in the UK it's about 75% diesel and 25% T8 hybrid

[Kev0607]

Originally Posted by anthv50

I've fitted a new aux belt and tensioner today, genuine parts direct from volvo, wallet £152 lighter and no fix. I've got it booked in a local garage for next week who suggested I did this first before they started buying parts to change to work out what it is. I'm 99% sure it's something ran by that belt, but it's beyond me to diagnose it further.

A video of the sound you're hearing may help. Post it here.

That's a shame that the aux belt and tensioner didn't fix it, but I suppose you won't need to change them for many years now.

[anthv50]

Originally Posted by Kev0607

A video of the sound you're hearing may help. Post it here.

That's a shame that the aux belt and tensioner didn't fix it, but I suppose you won't need to change them for many years now.

+ YouTube Video

[Kev0607]

Sounds like a rod knocking at the bottom end to me, but without being physically in front of it, its really hard to tell.

Like this, although this is a different engine (it sounds very similar)...

https://www.youtube.com/watch?v=HTV3UZSwlDw

[anthv50]

Originally Posted by Kev0607

Sounds like a rod knocking at the bottom end to me, but without being physically in front of it, its really hard to tell.

Like this, although this is a different engine (it sounds very similar)...

https://www.youtube.com/watch?v=HTV3UZSwlDw

which is why i put the thread as bearing failure because thats what it sounds like to me too. but it sounds absolutely fine when the aux belt was taken off.

[GrahamBrown1]

That certainly sounds very bottom endy. You say it’s not there with the aux belt removed? Did you rev the engine ect or just idle?

Does the noise go with the AC off? Normally pumps whine and I’m only trying to be hopeful in suggesting the AC compressor instead of engine. But the inside workings of an AC compressor with its numerous pistons eating itself could be fairly audible tho I’m not convinced but no harm in checking as you seem to think it’s in the belt area.

[anthv50]

Originally Posted by GrahamBrown1

That certainly sounds very bottom endy. You say it’s not there with the aux belt removed? Did you rev the engine ect or just idle?

Does the noise go with the AC off? Normally pumps whine and I’m only trying to be hopeful in suggesting the AC compressor instead of engine. But the inside workings of an AC compressor with its numerous pistons eating itself could be fairly audible tho I’m not convinced but no harm in checking as you seem to think it’s in the belt area.

I tried reving it a little, I am very scared of a piston making a bid for freedom so I wasn't going to rev it too much but it was definitely gone with no aux belt on.

I've just tried that, and when i switch it off the noise reduces for a second and then goes back.

I've had guys from two different garages come out and have a listen to it separately to see if they can book it in, and both said it's in the belt area, one said 95% it was to do with the aux belt system.

[GrahamBrown1]

Originally Posted by anthv50

I tried reving it a little, I am very scared of a piston making a bid for freedom so I wasn't going to rev it too much but it was definitely gone with no aux belt on.

I've just tried that, and when i switch it off the noise reduces for a second and then goes back.

I've had guys from two different garages come out and have a listen to it separately to see if they can book it in, and both said it's in the belt area, one said 95% it was to do with the aux belt system.

Hmm I can’t think of anything else belt related creating this noise. The auxiliary’s put load on the engine could it be with the belt removed the engine isn’t driving anything meaning no load and the noise reduces meaning it’s looking more likely it’s an internal engine fault. Hopefully you can get it looked at soon. Be interesting to hear the findings and hopefully it isn’t to costly.

[Kev0607]

Yes, it'll be interesting to hear what the garage finds. I hope its nothing too expensive, but now I've heard/watched that video, I'm led towards rod knock.

Update us when you can.

[anthv50]

I was doubting myself all night that I should have heard the noise with the belt off. So I've took it off again today, i'm getting MUCH quicker at doing it, and took another video for your viewing pleasure. It definitely sounds very different without the aux belt on. I've gave it a few revs in this one, not too much since it doesn't have the torque bar fitted to the mount. So I am not sure whether the load of the alternator and the turned off air con, would be enough to make it so loud.

+ YouTube Video