72 Vacum problem
Thread Starter
Heel & Toe
Joined: Sep 2010
Posts: 19
Likes: 0
72 Vacum problem
Need some help, headlights and wipers work fine but I have a line off under the dash and I don't know where it goes. The hose comes off a small vacum canister that is on the right side of the steering colum, there is also a electrical hook up to the canister. Little help please.
Thread Starter
Heel & Toe
Joined: Sep 2010
Posts: 19
Likes: 0
When I pull on the light switch, lights open and operate fine, to operate wipers I have to pull the the small post below the dash than the wiper door opens and I can turn on the wipers with the switch, should the wiper switch be like the lights? Turn the wiper switch on and the door opens and then wipers come on? From the picture the device that looks most similar is the small unit with the green and red line coming of it or it could be unit the has black line from switch and yellow out. Thanks for your help with this stuff.
Thread Starter
Heel & Toe
Joined: Sep 2010
Posts: 19
Likes: 0
To you others that helped, defroster seems to work as normal, but I will have a pay more attention when I check it tomorrow.
If I know how to identify the wiper solenoid I could check, Just got this car and I am trying to figure out all the various vacum operations. I am thinking of buying the manual for trouble shooting vacum problems.
If I know how to identify the wiper solenoid I could check, Just got this car and I am trying to figure out all the various vacum operations. I am thinking of buying the manual for trouble shooting vacum problems.
Burning Brakes
Joined: Jan 2010
Posts: 958
Likes: 88
From: Rexburg Idaho
When I pull on the light switch, lights open and operate fine, to operate wipers I have to pull the the small post below the dash than the wiper door opens and I can turn on the wipers with the switch, should the wiper switch be like the lights? Turn the wiper switch on and the door opens and then wipers come on? From the picture the device that looks most similar is the small unit with the green and red line coming of it or it could be unit the has black line from switch and yellow out. Thanks for your help with this stuff.
Le Mans Master
Joined: Jun 2005
Posts: 5,447
Likes: 3
From: Syracuse NY
Here's the wiper solenoid.
I marked the hose colors based on Willcox's diagram and the factory paint mark seen in my picture.
If this is hooked up correctly and in good working condition the wipers should work without touching that over-ride switch assuming all the other components of the wiper system are in good shape.
I think both Dr. Rebuild and Willcox have troubleshooting diagrams.
Well that didn't work out very well!
Where my thumb is, is where a little foam filter should be. Don't be surprised it that is missing but it wouldn't be a bad idea to replace it if it is.
The hose connection pointing to the right should have the blue striped hose, the one pointing up gets the yellow striped vacuum hose and the wires land up top too.
This solenoid was mounted to the backside of the tachometer from the factory.
I marked the hose colors based on Willcox's diagram and the factory paint mark seen in my picture.
If this is hooked up correctly and in good working condition the wipers should work without touching that over-ride switch assuming all the other components of the wiper system are in good shape.
I think both Dr. Rebuild and Willcox have troubleshooting diagrams.
Well that didn't work out very well!
Where my thumb is, is where a little foam filter should be. Don't be surprised it that is missing but it wouldn't be a bad idea to replace it if it is.
The hose connection pointing to the right should have the blue striped hose, the one pointing up gets the yellow striped vacuum hose and the wires land up top too.
This solenoid was mounted to the backside of the tachometer from the factory.
Last edited by DZRick; Sep 11, 2010 at 09:27 AM.
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Thread Starter
Heel & Toe
Joined: Sep 2010
Posts: 19
Likes: 0
I just looked, the foam filter is there and the disconnected hose is coming off the side port, but there is no hose attached to the brass end of the solenoid but the wires are attached. In the drawing, where is the yellow line going to, I can't tell what that is.
Le Mans Master
Joined: Jun 2005
Posts: 5,447
Likes: 3
From: Syracuse NY
Le Mans Master
Joined: Jun 2005
Posts: 5,447
Likes: 3
From: Syracuse NY
I should have said it tees off with one hose going to the headlight switch.
The headlight switch and the wiper door share the same vacuum source.
If you look at the diagram you'll see that the vacuum source (that's at your intake manifold) shown as black, it goes through a filter, then a check valve. From the upper port of the check valve it heads in under the dash where it hits a tee. One side of the tee ( shown in yellow ) goes to the solenoid, the other ( shown as black ) goes to the headlight switch.
Study the diagram, you'll see how everything is supposed to be hooked up. As far understanding completely what does what and when, well...
The headlight switch and the wiper door share the same vacuum source.
If you look at the diagram you'll see that the vacuum source (that's at your intake manifold) shown as black, it goes through a filter, then a check valve. From the upper port of the check valve it heads in under the dash where it hits a tee. One side of the tee ( shown in yellow ) goes to the solenoid, the other ( shown as black ) goes to the headlight switch.
Study the diagram, you'll see how everything is supposed to be hooked up. As far understanding completely what does what and when, well...