Its direct straight off the crank(sits before the crankshaft pulley).
Its a genuine one and me being me i checked it over fully for wear and tolerances compared to the old one and it looked in much better condition and tolerances were much lower than the aftermarket part that was on previously(so it must have been changed by one of the previous 2 owners)
check to see it hasnt stripped the gear, but only other thing i can think is that the pickup pipe hasnt got a seal fitted properly.
unsure on this engine but theres usually an o ring you push into the pick up pipe recess, slipping the ring over the pipe and pushing it up doesnt work. but im not sure on this engine, used to working on buses
