REMOVAL & INSTALLATION
1.5L and 1990 1.8L
See Figures 1, 2, 3 and 4
- Disconnect the negative battery cable. Remove the rocker cover. Matchmark the camshaft/rocker arm bearing caps to their cylinder head location, except 1.5L engines.
- Loosen the bearing cap bolts or the rocker shaft bolts on 1.5L engine, from the cylinder head but do not remove them from the caps or shafts. Lift the rocker assembly from the cylinder head as a unit.
- The rocker arm assembly can be disassembled by the removal of the mounting bolts and dowel pins on some vehicles, from the bearing caps and/or shafts.
Keep the rocker arms and springs in the same order as disassembly. The left and right springs have different tension ratings and free length. Observe the location of the rocker arms as they are removed. Exhaust and intake, right and left, are different.
See Figure 5
- Remove the rocker cover, timing cover and cylinder head from the vehicle. Remove the crank angle sensor.
- Remove both camshaft drive sprockets.
- Remove both rear (opposite end of the drive sprockets) camshaft bearing caps.
- Remove both front bearing caps and front oil seals.
- Remove the remaining camshaft bearing caps alternating from the rear of the head to the front.
- Remove the camshafts.
- Remove the rocker arms and the lash adjusters. Remove the valve body assembly from the rear of the cylinder head.
- Clean and inspect all parts. Check the rollers on the end of the rocker arms. If the rollers are worn or do not rotate smoothly, replace, as necessary.
- Install the lash adjusters and rocker arms. Lubricate them prior to installation. Install the valve body. Lubricate the camshafts. Place the camshafts in position. The intake side camshaft has a slit in the rear to drive the crank angle sensor. The bearing caps No. 2-5 are the same shape. When installing them, check the top markings to identify the intake or exhaust side. L or R is marked on the front caps, L for the intake side; R for the exhaust side.
- Tighten the bearing caps, in 2-3 steps, to 14-15 ft. lbs. (20-22 Nm).
- Make sure the rocker arm is properly mounted on the lash adjuster and valve stem tip.
- Install the front oil seals. Turn the intake camshaft until the front dowel pin is facing straight up at the 12 o'clock position. Install the crank angle sensor with the punch mark on the sensor housing aligned with the notch in the plate. Install the drive sprocket and tighten the bolts to 58-72 ft. lbs. (79-98 Nm). Install the rocker cover.
- Disconnect the negative battery cable.
- Remove the valve cover and discard the gasket.
- Remove the rocker shaft hold-down bolts gradually and evenly and remove the rocker shaft/arm assemblies.
- If disassembly is required, keep all parts in the exact order of removal. Inspect the roller surfaces of the rockers. Replace if there are any signs of damage or if the roller does not turn smoothly. Check the inside bore of the rockers and the adjuster tip for wear.
- Lubricate the rocker shaft with clean engine oil and install the rockers and springs in their proper places.
- Install the rocker shaft assemblies on the engine and tighten the bolts gradually and evenly. Torque the rocker shaft bolts to 23 ft. lbs. (32 Nm).
- Install the valve cover with a new gasket.
- Connect the negative battery cable.
See Figure 6
A special tool, MD998443 or equivalent, is required for this procedure.
- Disconnect the negative battery cable. Remove the rocker cover and gasket and the timing belt cover.
- Turn the crankshaft so the No. 1 piston is a TDC compression. At this point, the timing mark on the camshaft sprocket and the timing mark on the head to the left of the sprocket will be aligned.
- Remove the camshaft bearing cap bolts.
- Install the automatic lash adjuster retainer tool MD998443 or equivalent, to keep the adjuster from falling out of the rocker arms.
- Lift off the bearing caps and rocker arm assemblies.
- The rocker arms may now be removed from the shaft.
Keep all parts in the order in which they were removed. None of the parts are interchangeable. The lash adjusters are filled with diesel fuel, which will spill out if they are inverted. If any diesel fuel is spilled, the adjusters must be bled.
- Check all parts for wear or damage. Replace any damaged or excessively worn parts.
- Assemble all parts in reverse order of the removal procedures. Note the following:
- The rocker shafts are installed with the notches in the ends facing up.
- The left rocker shaft is longer than the right.
- The wave washers are installed on the left shaft.
- Coat all parts with clean engine oil prior to assembly.
- Insert the lash adjuster from under the rocker arm and install the special holding tool. If any of the diesel fuel is spilled, the adjuster must be bled.
- Tighten the bearing cap bolts, working from the center towards the ends to 15 ft. lbs. (20 Nm).
- Check the operation of each lash adjuster by positioning the camshaft so the rocker arm bears on the low or round portion of the cam pointed part of the can faces straight down. Insert a thin steel wire, or tool MD998442 or equivalent, in the hole in the top of the rocker arm, over the lash adjuster and depress the check ball at the top of the adjuster. While holding the check ball depressed, move the arm up and down. Looseness should be felt. Full plunger stroke should be 0.0866 in. (2.2mm). If not, remove, clean and bleed the lash adjuster.