Mercedes 112L & 113L Engine Cylinder head replacing procedure?
Replacing cylinder head details and diagrams for Mercedes Benz Truck Model Vehicles.
REMOVAL & INSTALLATION
Before servicing the vehicle, refer to the Precautions section.
Remove or disconnect the following:
Negative battery cable
Drain and recycle the engine coolant.
The fan clutch is equipped with right-hand thread.
Engine cooling fan and clutchFan shroud
Place a guard plate behind the radiator/condenser to protect it from damage during removal and installation.
Engine coverAir cleaner housing, resonance pipe and body
Properly relieve the fuel system pressure.
The intake manifold system must not be disassembled.
Fuel lineIgnition coilsCylinder head covers
Intake manifoldVacuum switchover valveCamshaft Position (CMP) sensor
Lock the automatic belt tensioner by rotating the tensioner counterclockwise until a 5mm drift or pin fits through the tensioner.
Serpentine beltHeater hose at left cylinder headDriver side fender linerExhaust support bracketPower steering pump and position it aside leaving the hoses attachedExhaust system from the exhaust manifolds
Rotate the engine clockwise to position the crankshaft 40 degrees after top dead center.
The engine must not be rotated backward.
Lock the camshafts using the Camshaft Locking tools 112 589 00 32 00 and 112 589 01 32 00.
Remove or disconnect the following:
Generator, then the timing chain tensionerOil filter housing and heat exchangerCamshaft gears and attach them to the chain with a cable tieCamshaft bearing bridgesTiming case-to-cylinder head bolts
Loosen and remove the cylinder head bolts in stages following the illustrated sequence.
Cylinder head off the engine blockAll gasket material from the sealing surfaces of the cylinder head and engine block. Be careful not to gouge or scratch the surface of the aluminum head. Be sure the cylinder head locating dowels are positioned in the engine block. Clean and dry the head bolt holes using compressed air.
Measure the length of the cylinder head bolt shafts, new bolt length is 5.57 inches (141.5mm) and the maximum permissible length is 5.69 inches (144.5mm). Replace bolts that measure greater than the maximum permissible length.
Fig. Exploded view of the cylinder head accessory components-M112 engines shown; M113 engines similar
Fig. Exploded view of the cylinder head removal-M112 engines shown; M113 engines similar
Fig. Cylinder head bolt removal sequence-M112 engines
Fig. Cylinder head bolt removal sequence-M113 engines
Fig. Cylinder head bolt tightening sequence-M112 engines
Fig. Cylinder head bolt tightening sequence-M113 engines
Clean the head bolt threads, then apply clean engine oil to the thread and head contact surfaces.
Install the cylinder head to the engine block and tighten the head bolts according to sequence as follows:
Step 1. 96 inch lbs. (10 Nm).
Step 2. 22 ft. lbs. (30 Nm).
Step 3. 90 degrees.
Step 4. additional 90 degrees.
Install or connect the following:
Timing case-to-cylinder head bolts and tighten to 15 ft. lbs. (20 Nm)Camshaft bearing bridgesCamshaft gear and tighten the mounting bolt to 37 ft. lbs. (50 Nm) plus an additional 90 degrees. Check the basic camshaft position and adjust if necessary.Timing chain tensioner with a new gasket and tighten to 59 ft. lbs. (80 Nm)Generator
Remove the camshaft locking plates.
Exhaust system to the manifolds and tighten the mounting nuts to 15 ft. lbs. (20 Nm)Heater hose to the cylinder headPower steering pumpSerpentine belt and remove the locking pinCMP sensorVacuum switchover valveIntake manifoldCylinder head covers and tighten the bolts to 89 inch lbs. (10 Nm)Ignition coils and tighten the mounting bolts to 70 inch lbs. (8 Nm)Fuel pipeAir cleaner housing, resonance pipe and bodyEngine cover
Remove the guard plate from the radiator/condenser.
Fan shroud, then the cooling fan
Fill the engine with coolant.
Connect the negative battery cable.
Read fault memory, encode the radio and normalize the power windows.