03-345 Checking and correcting setting of TDC pulse generator
Preceding work: Removing poly-V-belt (13-342). Removing cylinder head cover (01-406). Removing spark plugs (15-530). | Operation No. of operation texts and operation values or standard texts and flat rates |
P03-0025-36
Fan and fan shroud | remove and install (step 1). |
Engine | set to ignition TDC of cylinder 1 (step 2). |
No. 1 cylinder rocker arm bearing bracket | remove and install, 20 Nm (step 3). |
Valve spring | remove from 1st inlet valve, install (05-250). |
Valve stem seal | remove from 1st inlet valve, install (05-270). |
TDC setting | measure by attaching dial gauge holder |
Hexagon nut | unscrew at TDC pulse generator, withdraw TDC pulse generator (step 12). |
Dial gauge | slacken and set preload of 5 mm, position scale of gauge to "0" (step 13). |
Turn crankshaft | until dial gauge has moved back by 2.85 mm or 3.07 mm, respectively (step 14). |
Fixing device | Insert special tool 119 589 00 21 00 into setting slide. The pin in the vibration damper must engage in the groove of the fixing device; correct setting slide, if necessary (steps 14 through 19). |
Data
Piston travel at crankshaft setting | measured over inlet valve | 2.85 mm |
measured directly at piston crown | 3.07 mm | |
Special tools
119 589 00 21 00
136 589 04 21 00
001 589 53 21 00
Notes
The TDC pulse generator with bracket is attached to the timing case cover.
The pin in the vibration damper or on the belt
pulley must be positioned exactly below the
TDC pulse generator when the crankshaft is
positioned at 20° after TDC (arrow).
P03-2070-13
The setting of the TDC pulse generator must be checked or corrected:
When renewing the crankshaft or the vibration damper.
When renewing the timing case cover.
When fitting parts to reconditioned engines.
Checking
-------------------------------
1 Remove and install fan shroud (1) and fan (75), tightening torque of bolt (80), 25 Nm.
P20-0006-13
2 Set engine to ignition TDC of cylinder 1.
P01-2025-13
3 Remove rocker arm bearing bracket (61) of
cylinder 1; unbolt oil pipe for this step.
Tightening torque of bolts (63), 20 Nm.
P05-2039-13
4 Remove and install valve spring at inlet
valve 1 (05-250).
P05-2040-13
5 Remove valve stem seal of inlet valve 1,
install (05-270).
P05-2009-13
6 Mount valve on piston crown.
7 Turn back crankshaft to approx. 10° before TDC of No. 1 cylinder.
8 Bolt dial gauge holder 363 589 02 21 00 with threaded sleeve onto cylinder head stay bolt at front left.
P03-2038-13
Note
With cylinder head removed, mount a magnetic dial gauge holder onto the contact surface of the crankcase.
P03-2026-13
9 Insert dial gauge with extension.
10 Position tracer pin of dial gauge onto the
valve stem or piston crown with a preload of
2 mm.
11 Slowly turn crankshaft in direction of rotattion of engine until the larger pointer of the dial gauge stops (TDC setting).
P03-2055-13
12 Unscrew hexagon nut (1a) and withdraw TDC pulse generator (1).
P01-2001-13
13 Slacken dial gauge and mount extension with 5 mm preload onto the valve stem or piston crown. Turn scale of gauge until the large pointer is at zero.
14 Turn on crankshaft in direction of rotation until the dial gauge has moved back by the appropriate value (data in table).
P03-2055-13
15 Position fixing device 119 589 00 21 00 into the setting slide (2).
The pin on the vibration damper must engage in the groove of the fixing device (1).
If the pin does not engage, adjust position of setting slide.
P03-2033-13
Adjusting
-------------------------------
16 Slacken nut (2a) and move setting slide (2) far enough for the pin on the vibration damper to engage in the groove of the fixing device.
17 Tighten nut (2a) and withdraw fixing device.
P01-2001-13
18 Insert TDC pulse generator and screw on.
19 Take off dial gauge and dial gauge holder.