Manuals through 2025 now available!

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

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

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Vacuum Vent Valve: Testing and Inspection

The vacuum dump valve should be checked whenever brake application does not disengage the speed control.
1. Disconnect dump valve-to-actuator vacuum hose (with yellow stripe) at actuator.
2. Connect Rotunda Vacuum Tester 021-00037 or equivalent to end of hose at actuator.
3. Pump vacuum to approximately 10-15 inches.
4. Depress brake pedal. The vacuum should release.
5. If vacuum does not release, adjust or release vacuum dump valve.