Vacuum System
Thread Starter
Drifting
Joined: Apr 2005
Posts: 1,583
Likes: 10
From: Hilton Head Island SC
Vacuum System
I'll try and do this correctly this time. I have fixed my big vac problem on my 69. Now I have one left. When I start the car, the wiper door goes up, then back down in maybe 5 seconds. The door stays down until I turn on wiper switch, or start car next time. Any ideas? Thanks. Sorry for the previous thread screw ups.
Race Director
Joined: May 2006
Posts: 16,528
Likes: 53
From: Dayton, Ohio
You have a leak in the small hose part of your system.Probably the switch under the wiper arm.Pull the small hose off the relay under the RF fender and suck on it and see if it holds vacuum.If it doesnt backtrack until you find the source of the leak.
Race Director
Joined: May 2006
Posts: 16,528
Likes: 53
From: Dayton, Ohio
I guess I should have read your OP better you said it pops up on starting not when shutting off.Sounds like the entire system is bled down.Next time you get ready to start the car.Check to see if you have vacuum left in your tank.On the check valve-on the 2 hose side-remove one of the 2 hoses and see if there is vacuum there.
Last edited by ...Roger...; Aug 2, 2008 at 08:11 AM. Reason: spelling
Advanced
Joined: Apr 2008
Posts: 68
Likes: 2
From: Sydney NSW
As I understand it, it's the lack of vacuum (i.e vacuum being switched off) that operates the wiper door and headlight pop-ups, thus a hose off, or leak in a line, or a blockage/kink in a line, or very weak vacuum will make these things open.
Race Director
Joined: May 2006
Posts: 16,528
Likes: 53
From: Dayton, Ohio
Yes- no vacuum on the small hoses tells the wiper door or headlights to open.
Advanced
Joined: Apr 2008
Posts: 68
Likes: 2
From: Sydney NSW
I have the opposite problem at the moment: suddenly my wipers won't operate at all. When I move the wiper switch to high or low absolutely nothing happens. I haven't begun to diagnose it yet, but I'm hoping it's not the wiper door vacuum solenoid up under the dashboard that's faulty.
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