wiper door.
Thread Starter
Instructor
Joined: May 2010
Posts: 172
Likes: 3
From: Hesperia California
wiper door.
HI all, have replaced my vacuum filter and the vacuum check valve and when i first start my 69 350/350 the wiper door opens and then closes. the pull down vacuum controlls under the colum seam to be working properly under the hood all vacuum lines seam to be intact and ok any suggestions.
Race Director
Joined: May 2006
Posts: 16,528
Likes: 53
From: Dayton, Ohio
This is a starting point,with engine running,HL turned off,wipers off, pinch the small hose coming from the check valve and hold for 15 seconds, if the wiper door comes up you have a leak somewhere in the small hose circuit.
Thread Starter
Instructor
Joined: May 2010
Posts: 172
Likes: 3
From: Hesperia California
Thanks that sounds easy,oooohhhh so if i have a leak do you know where it might be, lol, thought that might be funny. But that will be a good start maby ill learn more and more as i go along. Getting pointed in the right direction sure helps. I guess the small line is the supply line yes.
Team Owner
Joined: Sep 2006
Posts: 31,270
Likes: 4,362
From: Westminster Maryland
Hi fv,
Roger's info is right on.
The small hoses are part of the 'control' side of the system... the vacuum turns the relays from 'close' to 'open' or back to 'close'.
The large hoses are the 'power' side of the system... the vacuum powers the 3 actuators to move the headlight and wiper doors up or down based on what signal the relays are sending.
When the doors open at start up it means the actuators are getting the vacuum power to move BEFORE they are getting the 'control' signal to stay where they are.
The 'small' hose system should always receive necessary vacuum before the 'large' hose system because of the size difference EXEPT if the 'control' side has a leak..... THUS Roger's suggestion to check for 'control' first.
If you don't have a trouble shooting guide think about buying the one from Dr. Rebuild. The systems are also easier to work on if you have a vacuum pump and gauge like a Mity-Vac.
Good Luck!
Regards,
Alan
Roger's info is right on.
The small hoses are part of the 'control' side of the system... the vacuum turns the relays from 'close' to 'open' or back to 'close'.
The large hoses are the 'power' side of the system... the vacuum powers the 3 actuators to move the headlight and wiper doors up or down based on what signal the relays are sending.
When the doors open at start up it means the actuators are getting the vacuum power to move BEFORE they are getting the 'control' signal to stay where they are.
The 'small' hose system should always receive necessary vacuum before the 'large' hose system because of the size difference EXEPT if the 'control' side has a leak..... THUS Roger's suggestion to check for 'control' first.
If you don't have a trouble shooting guide think about buying the one from Dr. Rebuild. The systems are also easier to work on if you have a vacuum pump and gauge like a Mity-Vac.
Good Luck!
Regards,
Alan
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Le Mans Master
Joined: Dec 2003
Posts: 5,727
Likes: 38
From: Fremont CA
I vote for pass side wiper arm not fully depressing the control valve in the wiper transmission area. Sometimes I'll install a glue-on rubber bumper onto wiper arm to make this hidden valve depress properly.
Thread Starter
Instructor
Joined: May 2010
Posts: 172
Likes: 3
From: Hesperia California
wiper door
7t1vette, you might have it. pinched off small hose after the check valve for 20 seconds wiper door stayed closed, checked other small hoses in wiper system same thing. Once i turned the *** between the two pull down vacuum valves under the collum and nuthing happoned waited abought 20 seconds then pulled down the wiper overide turned the *** again the pass side wiper came up abought 3 inches and right back down. So you are saying there is a valve that arm needs to push on to seal the vacuum in the system? As i said earlyer the problem is when i start up the car the wiper door opens up slowly and closes slowly if when its open i rev the engine to build up more vacuum it closes quicker.
