Note: A new oil pickup tube gasket and a new oil feed tube O-ring will be required during installation.
Removal
1. The oil pump is driven directly by the crankshaft and is located in the camshaft drive housing.
2. Remove the chain cover as described in paragraph 6.
3. Loosen the mounting bolts and remove the oil intake pipe (see fig. 13.3). Remove the gasket.
Fig. 13.3. Remove the oil intake pipe
4. Loosen the mounting bolts and remove the oil pump cover (see fig. 13.4).
Fig. 13.4. Remove the oil pump cover
5. Remove the inner and outer gears of the oil pump, remembering how they are installed (see Fig. 13.5, a, b).
Fig. 13.5, a. Remove the inner...
Fig. 13.5, b....and the external gear
6. Unscrew the bypass valve plug on the side of the camshaft timing chain housing, then remove the O-ring, spring and push rod (see Fig. 13.6, a-c).
Fig. 13.6, a. Unscrew the bypass valve plug...
Fig. 13.6, b....and remove the spring...
Fig. 13.6, c....and the pusher
Examination
7. Clean the parts thoroughly.
8. Check for scoring or wear on the inner and outer gears, gear teeth, cover and pump housing in the camshaft drive chain housing. If the gears are worn, they should be replaced as a set of gears. If the pump housing or cover is worn, a new chain housing must be installed. The new housing houses the new pump.
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9. Remove the sealing ring from the oil supply tube on the back of the pump and discard it (see fig. 13.9).
Fig. 13.9. Remove the sealing ring from the oil supply pipe
Installation
10. Install the inner and outer gears of the pump, then inject clean engine oil into the space between the two gears (see fig. 13.10).
Fig. 13.10. Inject clean engine oil into the space between the gears
11. Install the pump cover and tighten the mounting bolts to the required torque.
12. Install the new oil pickup tube gasket with the rounded edges of the gasket facing the top of the chain case.
13. Install the oil pickup tube and secure it with two bolts.
14. Install a new O-ring on the oil supply pipe from the back of the pump.
15. Lubricate the relief valve tappet with clean engine oil, then install the tappet, spring, sealing ring and plug. Tighten the plug to the required torque.
16. Install the camshaft timing chain cover as shown in paragraph 6.