UK Car Repair: excessive tappet noise, tappet noise, hydraulic lifters

Question
hi,my son is buying a w reg astra 16v gsi 88.000 miles.nice condition except for excessive tappet noise,firm selling has sent it,sent it to garage and all 16 hydraulic lifters were replaced and was shown old ones which looked like in new condition,but tappet noise is still not cured,i suspect either camshaft,followers,or not enough oil getting to the lifters.can you please help before he buys. regards brian

Answer
Any engine noise is a cause for concern, the fact that they have replaced these parts and still haven't cured it is ominous. In the first place, it is extremely unlikely that all the lifters would be bad, the engine has a more serious problem and I would suggest not buying it unless they can tell you exactly what it is, or, give you a warranty!