Hi,

Am about to acquire a used 91 318i with an M40 engine in it.

It has 200,000+km on it, and hasn't had any major work done to it in the last two years.

The tappets sound loud. I understand that these engines have self-adjusting hydraulic tappets? If so, what could be the cause of the tappet-like sound? Also, how big a job is it to replace/adjust the tappets?

Another issue is the timing belt on these engines. What is the replacement interval for these belts on the M40 engine, and is this an interference engine - the valves will be bent if the belt snaps? Thanks!