The North American B234F engines (16-valves) are interference, and will bend and break valves if a timing belt snaps. These engines were only available for 3 years, starting mid-year in 1989 in the 740 GLE, and during all of the two production years for the '90 740 GLE and '91 940 GLE. Only the 89-91 740/940 GLE cars received the 16-valve engines, and everybody else (GLs, Turbos, etc) got the standard 8-valve B230F or B230FT engines.

The North American Market B230F and B230FT engines (as equipped in most 200/700/940 vehicles from '85+) are not interference. No concern of bending valves. (8-valve system)

Some of the North American 760 and 780 vehicles from '87-'90 have the B280F 6-cylinder (12-valve) engine, which I believe is an interference design.

However, (if I recall correctly) several of the European spec B230 and B200 8-valve engines are interference and can bend/break valves if a timing belt snaps. It depends on the head and pistons that were fitted at time of manufacture. For example, the European B230 engines with the Heron head (introduced in '87) also received bowl/dished pistons that have valve relief to prevent interference, -but many B200 engines did not come so equipped. If someone has good documentation on the European interference issues, I'd be interested.

God bless,
Fitz Fitzgerald.

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'87 Blue 240 Wagon, 249k miles.
'88 Black 780, PRV-6, 145k miles.