Brake Fluid Replacement/Air-Bleed; Brake System - SANYANG INDUSTRY CO. SYM Service Manual

13. BRAKE
Remove the master cylinder cap and
diaphragm.
Add good quality brake fluid and it has to add
same brand brake fluid into the master cylinder.
Clean dirty brake disc.
CAUTION
The dirty brake lining or disc will reduce the
brake performance. The mixed
non-compatible brake fluid will reduce brake
performance. Foreign materials will block
the system causing brake performance to
be reduced or totally lost.
BRAKE FLUID REPLACEMENT/
AIR-BLEED
Connect drain hose to drain valve.
Open the drain valve on the caliper and hold
and release the brake lever alternatively until
the old brake fluid is entirely drained out.
Close the drain valve and add specified brake
fluid into the brake master cylinder.
CAUTION
To reuse the spent brake fluid will effect
brake performance.
Connect one end of transparent hose to the
drain valve, and put the other end into a
container.
Open the drain valve around 1/4 turns, and at
the same time hold the brake lever until the
there is no air bubble in the drain hose and
also feeling resistance on the brake lever.
Close the drain valve when finishing the
brake system refilling fluid procedure, and
operate the brake lever to check whether air
bubble is in brake system or not. If brake is
still soft, please bleed the system as
described below.
1. Tightly hold the brake lever and open the
drain valve around 1/4 turns, and then close
the valve.
CAUTION
Do not release the brake lever before the
drain valve is closed.
Always check the brake fluid level when
carrying out the air bleeding procedure to
avoid air entering into the system.
2. Slowly release the brake lever, and wait for
a few seconds until it reaches its top
position.
3. Repeat the steps 1 and 2 until there is no air
bubble at the end of the hose. Tightly close
the drain valve.
4. Make sure the brake fluid is in the UPPER
level of the master cylinder, and refill the
fluid if necessary.
5. Cover the cap.
13-6
Bubbles
SYM
master
cylinder
diaphragm
drain valve
Draining valve
Transparent hose