Vacuum Filter & Check Valves
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
The [mesh] filter in that plastic filter goes bad in just a few years. After that, the mesh is gone and it just doesn't do the filtering function anymore.
The check valve is very important and needs to operate properly for the system to work as intended.
The check valve is very important and needs to operate properly for the system to work as intended.
Racer
Joined: Feb 2007
Posts: 271
Likes: 25
From: Buena Vista Colorado
A symptom of a bad check valve is extension of one or both headlights during sustained wide-open throttle operation. Mine did that as we were climbing up local mountain passes.
Easy check valve test: Remove it from the car, put the large port to your lips (the one that was connected through the filter to the intake manifold), and attempt to blow through the valve. If you CAN blow through it, the valve is bad and should be replaced.
Easy check valve test: Remove it from the car, put the large port to your lips (the one that was connected through the filter to the intake manifold), and attempt to blow through the valve. If you CAN blow through it, the valve is bad and should be replaced.
Team Owner
Joined: Jun 2000
Posts: 38,923
Likes: 1,481
From: Southbound
Cruise-In II Veteran
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Safety Car
Joined: Sep 2011
Posts: 4,117
Likes: 1,230
From: Madeira Beach, FL
2024 C8 of the Year Finalist - Unmodified
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Just replaced my filter. You could see daylight straight through it.
I found one on a camaro site listed on ebay for 6 bucks.
When you look through a new filter it should have a white straining screen inside.
If you don't have to have AC stamped on the thing the after markets are cheap and do just the same.
I still have a slow opener on the right side head lamp door.
How do you get the right side to open simultaneously with the left
Marshal
I found one on a camaro site listed on ebay for 6 bucks.
When you look through a new filter it should have a white straining screen inside.
If you don't have to have AC stamped on the thing the after markets are cheap and do just the same.
I still have a slow opener on the right side head lamp door.
How do you get the right side to open simultaneously with the left
Marshal
Team Owner
Joined: Sep 2006
Posts: 31,266
Likes: 4,361
From: Westminster Maryland
Hi Marshall,
Does your 68 have 1 or 2 vacuum relays for the actuators?
If 1, then it has to be a leak in the 'open', (green striped hose), side of the actuator. It could be the seal on the acuator rod which can be replaced.
If 2, it could be a slow vacuum relay or actuator. Hook the left relay to the right actuator.... if it opens fast, it's the right side vacuum relay, if it's still slow it's the actuator.
Good Luck!
Regards,
Alan
Does your 68 have 1 or 2 vacuum relays for the actuators?
If 1, then it has to be a leak in the 'open', (green striped hose), side of the actuator. It could be the seal on the acuator rod which can be replaced.
If 2, it could be a slow vacuum relay or actuator. Hook the left relay to the right actuator.... if it opens fast, it's the right side vacuum relay, if it's still slow it's the actuator.
Good Luck!
Regards,
Alan
Safety Car
Joined: Sep 2011
Posts: 4,117
Likes: 1,230
From: Madeira Beach, FL
2024 C8 of the Year Finalist - Unmodified
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Alan,
thanks for the simple trouble shooting advise.
I have 1 relay centered under the hood and a left and right actuator.
I believe in 1969 they added the second relay.
I'll switch em and see
Marshal
thanks for the simple trouble shooting advise.
I have 1 relay centered under the hood and a left and right actuator.
I believe in 1969 they added the second relay.
I'll switch em and see
Marshal
Safety Car
Joined: Sep 2011
Posts: 4,117
Likes: 1,230
From: Madeira Beach, FL
2024 C8 of the Year Finalist - Unmodified
2024 C2 of the Year Finalist - Unmodified
2023 C2 of the Year Finalist - Unmodified
2020 C3 of the Year Finalist - Unmodified
Oops
only one relayso nothing to switch.
Should have read it twice before answering
I guess my P/S actuator is going.
Thanks again Alan.
Marshal
only one relayso nothing to switch.Should have read it twice before answering
I guess my P/S actuator is going.
Thanks again Alan.
Marshal
Melting Slicks
Joined: Apr 2001
Posts: 3,399
Likes: 278
From: Olmsted Falls, Ohio
Replace them both. They both will probably have gathered crud if the mesh is still intact.
My headlights were slow to open and one of them never closed all the way. I took the filters off and replaced them. Now the headlights come up quickly and close all the way.
Nice return on the investment of a couple of bucks.
My headlights were slow to open and one of them never closed all the way. I took the filters off and replaced them. Now the headlights come up quickly and close all the way.
Nice return on the investment of a couple of bucks.
