Headlight Vacuum Canister Testing
Thread Starter
Burning Brakes
Joined: Jan 2006
Posts: 1,154
Likes: 1
From: St Augustine FL
Headlight Vacuum Canister Testing
Is there a way to test the headlight vacuum canister to see if it is leaking down? My head lights will not raise with the motor off and only one will partially close with the motor off. With the motor running one headlight will raise (driverside) and then the other the same is true when closing. What else would/could cause this?
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
Is there a way to test the headlight vacuum canister to see if it is leaking down? My head lights will not raise with the motor off and only one will partially close with the motor off. With the motor running one headlight will raise (driverside) and then the other the same is true when closing. What else would/could cause this?
I think, this could be cause by a leaky passenger actuator or dust boot.
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
I believe there is also a rubber diaphragm in the back portion of that actuator that is prone to aging and cracking. I do not believe there is a rebuild kit which leaves only replacing it.
It's a rough system to try and trouble shoot. I'm guessing you have bought a remote vacuum gauge and tested your vacuum at all ports?
Also, have you tried switching the vacuum lines from one side to the other to see if the symptoms switch sides with the tubes? That might narrow it down to the left or right or the system as a whole.
Le Mans Master
Joined: Oct 2005
Posts: 6,247
Likes: 471
From: Glen Allen, VA
the way I did it was to put my finger over one inlet at a time and try to pull the arm in and out. When it wouldn't go in or out I knew it wasnt' leaking. At first with my finger over the back inlet, it would still go in and out, so I replaced the seals. I see you replaced your seals already, so yours may have an internal leak and have to be replaced.
Safety Car
Joined: Oct 2005
Posts: 3,570
Likes: 1
From: Algonac Michigan
I have found a few small leaks in my system where I thought there were none. Some were at a hose end that I thought was sealing well but in fact were not. All new hose in my rebuild. Some small zip ties corrected all problems, but you must have all good components first!
Mark
Mark
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