Vespa Primavera 50 - Service manual > Lubrication

Conceptual diagrams

The lobe pump "F" sucks the oil from the sump, through the mesh pre-filter "C", it pushes it into the cartridge filter "E" where there is also a safety valve "D".

Through the suitable passages found in the crankcases, the oil enters the crank chamber "G" where the main bearings are lubricated and the big end (with high pressure), the piston pin and connecting rod small end via spray "H".

Subsequently the oil arrives at the timing system where it lubricates the camshaft "A" and from this, valves and rockers. The oil passes through the timing chain duct and returns to the sump "B" by gravity.

In the system there is a minimal oil pressure sensor "I" and a spray that serves to lubricate the stator "L".

Oil pressure check

• After removing the flywheel cover as described in the "Flywheel" chapter, remove the electric connexion of the minimum oil pressure switch and then remove the switch.
• With the engine idling at 1750 rpm and the oil temperature at ~90ºC, check that the oil pressure is between 0.5 to 1.2 atm.
• With the engine idling at 5000 rpm and the oil temperature at ~90ºC, check that the oil pressure is between 3.2 to 4.2 atm.
• Remove the specific tools on the engine once the measurement is complete. Refit the oil pressure switch and washer, tightening it to the prescribed torque, and fit the flywheel cover.
• If oil pressure reading are not within the specified limits, check in the following order: the oil filter, the oil by-pass valve, the oil pump and the crankshaft seals.

N.B.

THIS CHECK MUST BE CARRIED OUT WITH OIL AT THE CORRECT LEVEL AND WITH AN OIL FILTER IN GOOD CONDITION.

Characteristic

Oil pressure
Operating pressure

• At 1750 rpm: (0.5 to 1.2)bar
• At 5000 rpm: (3.2 to 4.2)bar

Locking torques (N*m)
Minimum oil pressure sensor 12 - 14

Crankshaft oil seals

Removal

• Unscrew the three screws and remove them, complete with the copper gaskets.

• Using pliers remove the door by acting on the appendices.

• Remove the spacer and the O-ring.

Refitting

• Insert the components making sure to thoroughly grease the O-ring and the fork oil seal.
• Follow the steps in reverse order taking care to tighten to torque.

WARNING

IN ORDER TO PREVENT ABNORMAL FORMATIONS OF DIRT DUE TO THE RELEASE OF GREASE, WE RECOMMEND FIRST LUBRICATING THE SEAL RING STOPS WITH A BRUSH.

Locking torques (N*m)
Crankcase timing cover screws 11 - 13

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