On a 190D (OM601 engine), is there a simple test to check if the lifter are OK or not ?
And if just one lifter is worn, is it better to replace all the lifters or just the defective lifter ?

It's for a friend of mine whose his 190D is doing some clapping noise. The car has 130k.

Thank you.

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in France : 240D 1981 380 000 km
240D 1984 252 000 km
300D 1978 325 000 km
in the US : Ford Tempo 1993 70K