Discovery 300tdi auto

Hi, my truck has developed a noise like a collapsed bearing coming from top left of engine around the exhaust manifold. It's been getting louder over the past month so I thought I'd investigate. I've taken off the belt so it isn't the alternator bearings which I initially thought it was, and the rattle grating noise is still there as nasty on tick over as it is when reving. Any thought? Thanks

Snapped rocker shaft ?

Disco1BFG said:

Snapped rocker shaft ?

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Thanks. I'll check tmrw but surely the engine wouldn't start?

Well, it will start for a while, until it gives up the ghost properly, then you might have a sump full of sharp bits ( or maybe not ) - sometimes they'll run quite happily, sometimes they won't - depends where they've snapped..... easy fix if caught in time... - might need a new rocker or two... might not....

Disco1BFG said:

Well, it will start for a while, until it gives up the ghost properly, then you might have a sump full of sharp bits ( or maybe not ) - sometimes they'll run quite happily, sometimes they won't - depends where they've snapped..... easy fix if caught in time... - might need a new rocker or two... might not....

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Cheers. Will get back with what I find Thought it might be the turbo, will check that too.

Any doubts about the turbo and disconnect the inlet to the plenum and check for oil.. If you suspect either the turbo, or the rocker shaft, I wouldn't run it again until you've checked both. Could also be a rocker shaft stand bolt snapped, or loose..... or stripped

logman said:

Thanks. I'll check tmrw but surely the engine wouldn't start?

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Mine ran for four miles until some of the valve stem caps went down the pushrod holes.

Dragonwalker said:

Mine ran for four miles until some of the valve stem caps went down the pushrod holes.

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Oh flip.

Hi All, many thanks for your advice but it was the starter motor ring gear all mashed up. Replaced, now running nice until the next thing! Just one point, while searching I found many folk had isues with squeaky noise from the belt pulley areas. Same here, I canhged ever pulley and the last was the belt. It stopped the squeal for several weeks then it all came back. Changed belt for a more expensive one and the noise went for a few weeks but came back. Squirted literally, one short burst of WD and it disappeared but came back after a couple of miles. I now live with it haha.

Belt misaligned very common.remove belt release belt tensioner just enough to get a penny behind it in the 9 o'clock position worked for me and many others.

I'll tryt that. You mean wedge a penny behing it?

That's it then just do the nut up again and refit belt see how it sounds.

If anti-freeze from the coolant gets on the belt it will screech like a knackered bearing.