I'm chasing down a new anomolous noise somewhere in the engine bay. Fropm the cabin it sounds like a power sterring pump w/o fluid, a "gerotor" type noise.

Under the bonnet, man I cant find anything. Alt bearings a little weak. Water pump a bit whiney ( likely due to the recent cooolant LEAK), but here's the weird thing:

When I pop the oil fill cap, there is a very distinct "slapping" sound eminating from the valvetrain/engine. I dont remember my first diesel making any sort of such noise. There I could only hear the chain against the follower.( but that was with B100, which is quieter)

Is this common, or do I have a second pooched motor?

I just changed oil and will inspect filter carefully for metal.

Car runs fine, starts fine, just noisy. Someone please tell me its normal.

Sounds like alot of piston slap, but the piston slap I'm used to ( big block chevs) is more of swirly sound, not literally a slapping.