Vane Pump Mechanism - Lotus Evora Service Notes

Lotus Service Notes
- With the pump port axis vertical, check that the valve (lubricated with PAS fluid) falls smoothly into the
port. If any stickiness is apparent, replace the pump.
- Check the valve for leakage: Close off one of the ports in the side of the valve, and apply 450 kPa (65 psi)
of compressed air to the opposite port. No leakage from either end of the valve should be detected.
- Measure the free length of the flow control valve spring with a vernier caliper: Minimum = 29.2 mm
- Coat the valve with PAS fluid and instal with its spring. Fit a new 'O' ring on the pressure port union, lu-
bricate, instal and tighten to 69 Nm (51 lbf.ft).
9.

Vane Pump Mechanism:

- Remove the 4 bolts securing the pump rear housing, and withdraw the housing.
- Remove the snap ring from the pump shaft and withdraw the pulley and shaft assembly.
- Remove the pump rotor with its 10 vanes, followed by the cam ring and pump front plate.
- Pull out the shaft oil seal from the front of the housing, and press a new seal into position.
- Measure the thickness of each rotor vane: Specification = 1.405 - 1.411 mm
- Measure the side clearance between each vane and its rotor slot: Max. clearance = 0.03 mm
- Measure the pump shaft diameter and housing bush diameter and determine the oil clearance:
Max. clearance = 0.07 mm
- Refit the shaft and pulley assembly, taking great care not to damage the oil seal.
- Fit new 'O' rings to the housing and front plate and lubricate with PAS fluid, before inserting the plate into
the housing with the notch on the rear side rim aligned with the notch in the housing.
- Fit the cam ring into the housing with the inscribed mark facing rearwards, and the notch aligned with the
notch in the front plate.
- Fit the vane rotor onto the shaft and lubricate before sliding the 10 vanes into their slots.
- Retain the rotor by installing a new snap ring into the shaft groove.
- Fit a new 'O' ring into the groove in the rear cover, and fit the cover to the housing so that the alignment
pin engages into the notches in the cam ring, front plate and pump housing. Fit the 4 retaining bolts and
tighten to 22 Nm.
- Check Preload: Fit a M10 x 1.25 x 50mm bolt into the pulley end of the shaft, and apply a torque wrench
to the bolt. Check pump rotation torque; Max. = 2.8 kgf.cm (2.4 lbf.in).
10. If necessary, fit a new PAS pressure switch with lubricated 'O' ring, and tighten to 21 Nm.
11. Before installing the pump, insert the upper bolt through the top lug on the pump housing. Fit the pump
to the engine and secure with the upper and lower bolts. Tighten both fixings to 43 Nm (32 lbf.ft).
12. Plug in pressure switch connector. Fit banjo bolt with two new washers and connect high pressure pipe
to outlet union. Tighten to 50 Nm (37 lbf.ft). Connect the reservoir hose to the pump spigot and secure
the clamp.
13. Refit the auxiliary drive belt to all pulleys, ensuring that the belt ribs are correlty located on each drive
pulley. Rotate the tensioner counterclockwise to relieve tension, and remove the tensioner locking pin.
14. Refill and bleed the PAS system (see above), and check for leaks.
15. Refit rear clamshell (see sub-section BV.6).
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Section HI