[john walker's workshop]

best to do a full rebuild as necessary, rather than just the syncro. there will be plenty of parts inside that are somewhat worn.
it's easier to do a valve adjust on a 930 when the engine is out. cheaper too. the clutch should be looked at. oil leaks from the engine thermostat, oil light switch and breather hose are easier to get at too.
tighten all the intake nuts. they're always loose on 930s. CV joints probably need servicing. boots as necessary.