Supplementary Work For Basic Throttle Setting
Supplementary Work For Basic Throttle Setting (S62)
This work is carried out:
- on engines with adjustable pull rods at both cylinder banks
- if the throttle opening of 24.2 mm ± 0.5 mm cannot be achieved when the full-load adaptation stop is set
The non-adjustable pull rod (1) of cylinder bank 1-4 is replaced by an adjustable pull rod (2) (versions as on cylinder bank 5-8).
Clip in adjustable pull rod (2) of cylinder bank 1-4 on throttle side only.
Clip in adjustable pull rod of cylinder bank 5-8 on throttle and servomotor sides.
Turn back stop screw (1) a few turns.
This ensures that the stop screw does not influence the servomotor-side stop.
Activate servomotor at specified value 100 % and check whether measurement (A) = 24.2 mm ± 0.5 mm is achieved.
If measurement (A) > 24.2 mm ± 0.5 mm, shorten pull rod of cylinder bank 5-8 by turning hexagon (1) until measurement (A) = 24.2 mm ± 0.5 mm is achieved at all throttles 5-8.
Screw in stop screw (1) until front end of screw rests on stop lug.
Activate servomotor at specified value 0 %.
Synchronizing cylinder banks with each other:
Position adjustable pull rod (1) of cylinder bank 1-4 on servomotor side on ball head.
Turn hexagon to adjust length of pull rod (1) so that ball socket is aligned centrally to ball head.
NOTE: Do not clip in pull rod (1) yet.
Force off adjustable pull rod (2) of cylinder bank 5-8 on servomotor side.
Position dial gauge plates on throttle body of cylinders 2 and 3 and throttle body of cylinders 6 and 7. Mount dial gauges in dial gauge plate supports for measuring at throttle bodies 3 and 6.
NOTE:
To simplify synchronization, correct height of dial gauges in such a way that large needles point upwards.
Turn dials on both dial gauges so that large needles point to zero.
Gently open and close each throttle bank several times to check if the large needles are always pointing to zero. If necessary, correct dials.
Clip in both pull rods (1) and (2) on servomotor side.
NOTE: Because of the closing force of the return spring in the servomotor, one or both dial gauge(s) can display a slight deviation from zero (approx. 0.01 mm). Do not correct dials on dial gauges.
Activate servomotor at specified value 1 %.
CAUTION!
Do not open throttles by hand.
Servomotor shaft with twin lever would thus receive a different radial position. This would result in an incorrect measurement result and incorrect throttle setting.
When the servomotor is activated at specified value 1 %, throttles 3 and 6 are opened to such an extent that the dial gauges indicate a change between 0.2 mm and 0.4 mm. Check whether both dial gauges indicate the same value. If necessary, turn hexagon head on adjustable pull rod 1-4 slightly until both dial gauges indicate the same opening value for throttles 3 and 6.
Enter specified value of 0 % and re-enter specified value of 1 %. Check whether both dial gauges indicate the same opening value for throttles 3 and 6.
Deviation between both dial gauges must be less than 0.03 mm.
CAUTION!
As the engine wiring harness is only partially mounted, fault messages are stored in the DME control unit.
Remove sealing flange for intake air manifold on left (cylinders 5 to 8).
Assemble engine.
NOTE:
Interrogate fault memory of DME control unit.
Check stored fault messages.
Rectify faults.
Now clear the fault memory.