Homemade Vacuum System Tester
C3 owners:
While sorting through some old Corvette magazines, I ran across this November 1993 "Corvette Fever" article showing how to make a vacuum system tester using an old propane tank, standard plumbing ball valves and a vacuum gauge.
To set up, disconnect the vacuum hose at the intake manifold that feeds the car's vacuum tank, connect valve 1 (input) to the intake manifold port and valve 2 (outlet) to the hose you disconnected.
To use:
Charge tank mode- With all valves open: Start engine to charge tank and car's vacuum system until gauge reads 10" hg or more. If you can't build vacuum, close valve 3 to and try again. If closing valve 3 makes a difference, there's a major vacuum leak in the car's system.
Diagnostic mode #1- Close valve 1, shut off engine, then open valve 3. This keeps the car's vacuum system charged with the engine off so you can listen for leaks while checking system operation by using headlight, wiper door, and HVAC vacuum controls.
Diagnostic mode #2- Close valve 2: This performs a leak down test for car's system by checking for a stable vacuum gauge reading.
I need to check my system for leaks, so I think making this tool will be a holiday project.
Home made vacuum tank 1.jpgHome made vacuum tank 2.jpg
While sorting through some old Corvette magazines, I ran across this November 1993 "Corvette Fever" article showing how to make a vacuum system tester using an old propane tank, standard plumbing ball valves and a vacuum gauge.
To set up, disconnect the vacuum hose at the intake manifold that feeds the car's vacuum tank, connect valve 1 (input) to the intake manifold port and valve 2 (outlet) to the hose you disconnected.
To use:
Charge tank mode- With all valves open: Start engine to charge tank and car's vacuum system until gauge reads 10" hg or more. If you can't build vacuum, close valve 3 to and try again. If closing valve 3 makes a difference, there's a major vacuum leak in the car's system.
Diagnostic mode #1- Close valve 1, shut off engine, then open valve 3. This keeps the car's vacuum system charged with the engine off so you can listen for leaks while checking system operation by using headlight, wiper door, and HVAC vacuum controls.
Diagnostic mode #2- Close valve 2: This performs a leak down test for car's system by checking for a stable vacuum gauge reading.
I need to check my system for leaks, so I think making this tool will be a holiday project.
Home made vacuum tank 1.jpgHome made vacuum tank 2.jpg