Power Brake Booster Check Valve Test

1. Disconnect vacuum hose from check valve.
2. Remove check valve and valve seal from power brake booster.
3. Use a hand operated vacuum pump and apply 15-20 in. Hg vacuum at large end of check valve. See Fig 1.
4. Vacuum should hold steady. If gauge on pump indicates vacuum loss, check valve is faulty and should be replaced.

Fig 1: Testing Power Brake Booster Check Valve

Courtesy of CHRYSLER CORP.