VESPA PX 150 USA, Workshop Manual

Page: 83 / 138

Fill
Front
−
Once the bleeding valve is shut, top-up the circuit using fresh brake fluid.
−
Loosen the bleed screw.
−
Connect the special tool's tube to the bleed hole. To bleed the system, constantly refill the reservoir,
while pumping out air with the Mityvac, until all air has been removed from the circuit, i.e. only fluid is
pumped out of the system.
−
Tighten the bleed screw.
N.B.
IF AIR CONTINUES TO COME OUT DURING PURGING, EXAMINE ALL THE FITTINGS:
IF SAID FITTINGS DO NOT SHOW SIGNS OF BEING FAULTY, LOOK FOR THE AIR INPUT AMONG
THE VARIOUS SEALS ON THE PUMP AND CALLIPER PISTONS.
CAUTION
- DURING THE OPERATIONS, THE VEHICLE MUST BE ON THE STAND AND LEVEL.
N.B.
DURING PURGING FREQUENTLY CHECK THE LEVEL TO PREVENT AIR GETTING INTO THE
SYSTEM THROUGH THE PUMP.
WARNING
THE BRAKE FLUID IS HYGROSCOPIC, I.E. IT ABSORBS HUMIDITY FROM THE AIR. IF THE HU-
MIDITY LEVEL IN THE FLUID EXCEEDS A GIVEN VALUE, THE BRAKING PERFORMANCES MAY
SERIOUSLY DETERIORATE. IT IS THEREFORE RECOMMENDED THAT FRESH FLUID IS TAKEN
FROM NEW CONTAINERS. IN NORMAL CLIMATIC CONDITIONS, THE FLUID SHOULD BE RE-
PLACED EVERY TWO YEARS. IF THE BRAKES ARE HIGHLY STRESSED, INCREASE THE
FREQUENCY WITH WHICH THE FLUID IS REPLACED.
CAUTION
WHEN CARRYING OUT THE OPERATION, BRAKE FLUID MAY LEAK FROM BETWEEN THE
BLEED SCREW AND ITS SEAT ON THE CALLIPER. CAREFULLY DRY THE CALLIPER AND DE-
GREASE THE DISC SHOULD THERE BE BRAKE FLUID ON IT.
Recommended products
AGIP BRAKE 4 Brake fluid
FMVSS DOT 4 Synthetic fluid
With the operation concluded, tighten the bleed
screw to the prescribed torque.
Specific tooling
020329Y MityVac vacuum-operated pump
Locking torques (N*m)
Oil draining screw
10÷12
Vespa PX 150 USA
Braking system
BRAK SYS - 83