Setting the Timing

Setting the timing








Warning: Never twist the crankshaft the direction of movement!
Proceed carefully and accurately when setting the timing as otherwise the engine can be damaged!
Only turn the engine on the crankshaft and never on the camshaft as the timing chain can jump over!

Note:
^ The timing is always set simultaneously on both cylinder banks. Once a cylinder bank has been set, the crankshaft must not be turned to set the other cylinder bank!
^ The fastening screws on the sprocket wheels do not need to be replaced after they have been undone.
^ The screws on the sprocket wheels are tightened by hand during assembly end are then loosened by one or two turns. This play is necessary so that the camshafts can still be turned.
^ The cylinder bank is set with the standard chain tensioner that is installed.

Preliminary check of the timing





1. Remove the camshaft housing cover on both cylinder banks.

Note: To remove the play from the timing chain for the setting process, the crankshaft must be positioned at least 45° in front of the TDC of cylinder 1 before turning!





2. Using socket wrench insert 9714, turn the crankshaft until cylinder 1 is located in the ignition TDC. Insert fixing pin 9595/1 into the revelant groove in the timing chain housing cover through the bore provided in the crankshaft gearwheel.





3. Ensure that the cams on cylinder 1 face upwards (ignition TDC).

Note: If the cams on cylinder 1 are not positioned as shown, check whether the crankshaft needs to be turned through another turn (360°)!





4. Simultaneously fix both cylinder banks (1-4 and 5-8) in the rear grooves of the camshafts using camshaft ruler 9678. The timing is correct if the camshaft rulers on both cylinder banks fit into the rear camshaft grooves and fixing pin 9595/1 fits into the relevant groove of the timing case cover through the bore provided in the crankshaft gearwheel.





View shows position of cams on cylinder 1





View shows position of cams on cylinder 5





View shows TDC position of crankshaft

Setting the timing
^ The crankshaft is positioned in the TDC and is fixed using fixing pin 9595/1 once the above preliminary check has been performed.





1. Undo all four fastening screws from the camshaft wheels on both cylinder banks. To do this, counter the hexagon (a/f 32) of the camshaft wheel on the corresponding camshaft with the ring wrench and undo the M12 pan-head screw by 1 or 2 turns using the T60 socket wrench insert.





2. Turn the camshaft on the hexagon with an open-ended wrench until camshaft ruler 9678 can be pressed back into the grooves of both camshafts simultaneously.

Figure shows the camshafts fixed with camshaft ruler





Note: Cylinder banks 1-4 and 5-8 are adjusted without turning the crankshaft!

3. Then adjust the camshafts on cylinder bank 5-8. To do this, turn the hexagon with the open-ended wrench and fix it with camshaft ruler 9678.

Correct positioning of cams in cylinder bank 5-8





Note: The fastening screws on the sprocket wheels do not need to be replaced after they have been undone.








4. Tighten all camshaft wheels with the M12 pan-head screw again. To do this, counter the hexagon (a/f 32) of the corresponding camshaft wheel with a ring wrench and tighten the M12 pan-head screw with the T60 socket wrench insert.
5. Remove camshaft ruler 9678 and fixing pin 9595/1
6. Turn engine through two turns (720°) and check the timing again.
7. Install the camshaft housing cover on both cylinder banks.





Tightening torques