When I start the car, when its been sitting a while (engine ambient temp), and don't let it warm up for more than a 4-5 min.'s + I hear mild rhythmic tapping from the engine valve train area almost like the sound of a diesel until the engine becomes warm.

The car has 52K miles and has always been in for scheduled service.

Should I have any concern here? Is there any adjustments necessary??

The sound is mild and consistent and then goes away. Performance seems fine, there's no oil burning and I always use hi-test gasoline.

Response appreciated.

Although mileage is premature for this, could be chain - which is possibly loose in your case, until tensioner kicks-in.

I think his tensioner is of the spring/ratchet type, not the oil pressure type. It should provide adequate tension at all times.

__________________
Michael LaFleur

'05 E320 CDI - 86,000 miles
'86 300SDL - 360,000 miles
'85 300SD - 150,000 miles (sold)
'89 190D - 120,000 miles (sold)
'85 300SD - 317,000 miles (sold)
'98 ML320 - 270,000 miles (sold)
'75 300D - 170,000 miles (sold)
'83 Harley Davidson FLTC (Broken again) :-(
'61 Plymouth Valiant - 60k mikes
2004 Papillon (Oliver)
2005 Tzitzu (Griffon)
2009 Welsh Corgi (Buba)

Well gentleman it appears that what I hear should not be a big concern at least for the forseeable future. Thank you for your responses.
DSR

Can very well be an injector.
This car has electronic FI and a dirty/worn injector will tap.
Can be easily found with a stethoscope or un-plugging when heard.

Arthur,
Nice to see your response.......Your advise on the OVR was dead on. No problem since. Without a doubt I know I would have been draged thru the coals at the local MB dealer and it was a easy change out. I also appreciate the lead on this site. It's great to read and share with other MB owners. I'll check out your suggestion in the bad injector(s).
TIA