Hi, I have a 2008 xf 2.7d. When I try to start it it seems as if it's trying to start maybe on one bank, then seems to lock as if there is mechanical contact. It's done 110000 miles, I,ve removed timing belt covers and belt appears intact but when turning over by hand at certain points there is definite resistance (not just compression) Are these engines known to drop valves? and where can I find information regarding the belt timing marks.
Thankyou