Disco 1 Clack clack clack what the hell is that

Had this noise for a while louder when cold softens up when warm had a good prod around with long screwdriver seems to be loudest on no1 cylinder head bolt the one closest to the front IP (edc) side .changed the cylinder head (unrelated job) due to multiple cracks and the noise stopped the engine sounded fantastic for 200 miles but now it's back and a bit stumped where to go with this not sure if cylinder head has failed no sign of gasket failure rechecked valve clearances all ok there.to me it sounds like mild piston slap but checked cylinder bores no sign of uneven wear and the spiral Finnish on wall looked fine and even over all cylinders any ideas as it drives great but sounds like a bag of doo doo.

Valve wobble? Camshaft wear? 200, 300, V8 ?

Valve stem clearances need adjusting again?

Mine started clattering worse than usual, and it was that one of the stem caps had worn through! Couldn't see it from the side easily, as the side of the cap was still in place, but the clearance was suddenly way out.

It's a 300tdi edc.had a valve cap break up myself in the pass not that sort of sound plus already checked when rechecked clearances.cylinder head was second hand skimmed and pressure tested so checked valve guides for wear again all ok.good thought on the camshaft didn't even consider that one.if I remove the timing belt and rocker assembly will I be able to feel any play?.

I was thinking more uneven lobe wear than bearings...bit of a stretch, I know, but I have been playing with Ford built Volvos of late and now my mind runs on strange rails.
Could one the feel slack in bearings? Yes, if there was lots, but all the various tensions when running could bring it out. Maybe.
How does it start from cold? Do you have the EDC, top-of-the-head, cold start sensor problem? Cylinder head, that is, not your head. Lemsip would be the thing for that...if it was your head.

Right finally had time to have a better look top of no1 injector is the loudest by far no2 can still hear noise but softer.also very loud on the injection pump but think it's the knock from the injector vibrating back down the line.bad injector releasing too early or late pre ignition/detonation ?.cold starts are poor always have to heat plugs if I don't will take forever to start.

mr glee said:

Right finally had time to have a better look top of no1 injector is the loudest by far no2 can still hear noise but softer.also very loud on the injection pump but think it's the knock from the injector vibrating back down the line.bad injector releasing too early or late pre ignition/detonation ?.cold starts are poor always have to heat plugs if I don't will take forever to start.

Click to expand...

have you tried slackening the injector union whilst its running, and previously did piston have round marks in the carbon were valves had touched

Did you put the injectors from the old head into the new one? Sounds like it could be a dodgy injector nor opening/ closing properly

There was no sign of contact on the pistons and old injectors where used tried cracking off the injectors the noise remains can't hear it on the cylinder head or block but all injectors and pipes have the same clack even when cracked off beginning to think it's the IP that's making the noise