Manuals through 2025 now available!

Our trusted friends have launched a new website named LEMON, which has newer manuals. It also contains all the CHARM manuals.

LEMON is the spiritual successor to CHARM, I recommend you try it!

Link: lemon-manuals.la or lemon-manuals.org.ua

(Some people have issue connecting. LEMON is investigating. For now, use Firefox or change your DNS server)

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Hydraulic System: Service Precautions

The booster is a tandem vacuum-suspended unit. Without the brake pedal depressed, the booster operates with the vacuum on both sides of its diaphragms. When the brake pedal is depressed, air at the atmospheric pressure is admitted to one side of each diaphragm to provide power assist. When the brakes are released the air is shut off from that side of each diaphragm. The air is then drawn from the booster through the vacuum check valve to vacuum source.