Exhaust Heat Control Valve
- Visually inspect valve for damage, repair or replace as necessary. Check that vacuum source is working. If a vacuum check valve is used, it must be checked for proper operation.
- Using a hand-held vacuum pump, apply vacuum to exhaust heat control valve vacuum motor and hold for one minute. Butterfly valve must start to close at 3.-6 in. Hg and be completely closed at 10 in. Hg.
- Vacuum motor must not leak more than 2 in. Hg of vacuum when 15 in. Hg of vacuum is applied. Butterfly valve must return to full open position when vacuum is released.
NOTE:
The butterfly valve is considered closed when shaft lever comes within 0.065" (1.7 mm) of stop.