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1B3-136 OM600 ENGINE MECHANICAL
I Length of Valve
w Camshaft Cam Basic Circle Diameter x Distance (Camshaft basic bore - valve stem) y Half Camshaft Basic Bore Diameter
z Distance (Cylinder head cover parting surface - . valve stem)
8. Measure ‘x’ (Camshaft basic bore - valve stem).
‘ x ’ = ‘ z ’ - ‘ y ’
9. Determine the valve to be used.
(See ‘Matching valves ’)
Example) Measured value ‘w’ = 38.2 mm
Measured value ‘z’ = 36.5 mm
Value ‘y’ = 15.5 mm
‘x’ = 36.5 - 15.5 = 21.0 mm
In the case of a camshaft cam basic circle diameter
‘w’ = 38.2mm and a distance ‘x’ = 21.0mm, the installed
valve may be used.
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OM600 ENGINE MECHANICAL 1B3-137
CAMSHAFT TIMING TEST Preceding Work : Removal of glow plug
1 Cylinder Head Cover
2 Bolt............................................................ 10Nm
3 Gasket ................................................... Replace 4 Valve Tappet
5 Cylinder Head
Timing
Condition of camshaft New
After approx. 20,000km Intake valve
Open
ATDC 11.33 °
ATDC 12 ° Close
ABDC 17 °
ABDC 18 ° Exhaust valve
Open
BBDC 28 °
BBDC 27 ° Close
BTDC 15.25 °
BTDC 14 °
At 2mm of valve lifting stroke.
Page 403 of 1574

1B3-138 OM600 ENGINE MECHANICAL
6. Check the timing.New
After approx. 20,000km ATDC 11.33
°
ATDC 12 °
Notice If timing is out standard, the camshaft should be checked for wear and the timing chain for stretch. If a difference of more than 4 ° exists, the timing chain should be replaced.
7. Replace the gasket and install the cylinder head cover.
Tightening Torque 10 Nm
Measurement Procedure
1. Remove the cylinder head cover.
2. Rotate the engine in the direction of engine rotation until the intake valve of NO. 1 cylinder is completely closed. The cam lobe faces up (arrow). Notice Do not rotate the engine at the bolt of the crankshaft sprocket. Do not rotate the engine in the opposite directionof engine rotation. If do, this will cause serious measuringerrors.
3. Install the dial gauge holder and dial gauge (7) with theextension (8) to the cylinder head and position the tracer pin (9) onto the valve tappet (intake valve of cylinder NO.1)with a preload of min. 3mm. Notice The tracer pin should be positioned exactly vertical.
Dial gauge Holder 363 589 02 21 00Dial Gauge 001 589 53 21 00Extension 366 589 00 21 05
4. Set the dial gauge to ‘0’.
5. Rotate the engine further in direction of rotation until the dial gauge has moved back by 2mm (valve lift) to 1mm.
Tools Required 001 589 53 21 00 Dial Gauge363 589 02 21 00 Dial Gauge Holder366 589 00 21 05 Extension
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OM600 ENGINE MECHANICAL 1B3-139
CAMSHAFT Preceding Work : Removal of cylinder head cover
1 Bolt............................................................ 25Nm
2 Washer
3 Camshaft Bearing Cap
4 Camshaft
5 Dowel Pin
6 Locking Washer
7 Timing Chain 8 Cylinder Head
9 Oil Pan
10 Camshaft Sprocket
11 Washer
12 12-Sided Bolt (M11) ... ..........Check, 25Nm + 90 °
13 Gasket ................................................... Replace
14 Chain Tensioner ........................................ 80Nm
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1B3-140 OM600 ENGINE MECHANICAL
3. Remove the starter motor and install the engine lock.Engine Lock 602 589 00 40 00
Tools Required 602 589 00 40 00 Engine Lock Removal Procedure
1. Rotate the crankshaft and position the piston of no.1 cylinder
at TDC. Notice Do not rotate the crankshaft in the opposite direction of engine rotation. In this position, the markings of the camshaft/camshaft bearing cap (arrow) must be aligned.
2. Place alignment marks on the camshaft sprocket and timing chain.
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OM600 ENGINE MECHANICAL 1B3-141
4. Remove the bolt and then remove the camshaft sprocket.Notice During removal, be careful not to drop the sprocket with chain. Remove the chain carefully and then pull out thesprocket.
5. Remove the chain tensioner.
6. Remove the camshaft bearing cap bolts according to the removal order. Notice Remove the camshaft bearing cap bolts of 1(dark arrow) first and then remove the bolts of 2 (light arrow) one revolution in stages until the counter-pressure is released. In order to avoid damaging the camshaft, it is essential toadhere to the removal order for the camshaft bearing caps.
OM 662LA
OM 661LA
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1B3-142 OM600 ENGINE MECHANICAL
4. Install the camshaft bearing caps according to markings(1,2, 3 etc.).
7. Remove the camshaft bearing cap.
8. Pull off the camshaft.
Notice
Be careful not to miss front locking washer.
9. Pull out the locking washer.Notice Check the condition of locking washer and replace if
necessary.
Installation Procedure
1. Insert the locking washer.
2. Check the valve tappet and ensure that tappet moves smoothly.
3. Coat the camshaft with oil and install the camshaft onto the cylinder head so that the TDC marking (arrow) is positioned
upward vertically.
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OM600 ENGINE MECHANICAL 1B3-143
5. Tighten the camshaft bearing cap bolts acccording toinstallation order.
6. Install the camshaft sprocket to be aligned the markings of the camshaft / camshaft bearing cap (arrow). Notice Align the alignment marks on the timing chain and sprocket.
Tightening Torque 25 Nm
Notice
Tighten the No. 1 bolts (light arrow) by one revolution in stages first and then tighten the No.2 bolts (dark arrow).
OM 661LA
OM 662LA
7. Tighten the camshaft sprocket bolt.
Tightening Torque 25Nm + 90 °