Testing windshield wiper door actuator valve???
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Testing windshield wiper door actuator valve???
1972 Vette, can anyone tell me how to test the w/s wiper door actuator valve that bolts to the firewall? Want to be sure it's good before I get too far in the rebuild process. There is no engine in the car so I can't use the vacuum from the engine to test it. Thanks for your help, Bob
Last edited by Cigars4me; Mar 12, 2018 at 02:46 PM.
Team Owner
Joined: Sep 2006
Posts: 31,135
Likes: 4,206
From: Westminster Maryland
Hi ZO6,
I'm not sure what part you're referring to because of.... "bolts to the firewall'.
The actuator itself?
The actuator relay?
The wiper door 3 Port Interlock Switch?
There's a test process for each of them but each is a little different.
Regards,
Alan
Actuator:
Actuator Relay:
3 Port Interlock Switch:
I'm not sure what part you're referring to because of.... "bolts to the firewall'.
The actuator itself?
The actuator relay?
The wiper door 3 Port Interlock Switch?
There's a test process for each of them but each is a little different.
Regards,
Alan
Actuator:
Actuator Relay:
3 Port Interlock Switch:
Last edited by Alan 71; Mar 12, 2018 at 04:05 PM.
Former Vendor
Joined: Aug 2006
Posts: 76,656
Likes: 1,850
From: Jeffersonville Indiana 812-288-7103
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15
There are two videos on youtube on how to do this.. one is wrong.. ours is 100 percent correct. Testing the valve should always be done on the middle tit on the valve, not the lower. When the valve is open (arms up and working) the valve should block vacuum on the lower port. When the arms park the vacuum should pass from the middle tit to the lower one. Testing on the lower tit for blocking vacuum, we'll its just not smart. If you look at the vacuum schematic you'll see that the pulling vacuum comes in on the middle tit and has to be blocked from the lower to function properly. It's possible for a valve to block on the lower tit and still leak vacuum on the upper.... this is the main reason the imported wiper valves are junk... they block but leak.
Actuator testing:
Willcox
69-72 Wiper Arm Vacuum Relay testing.
Actuator testing:
Willcox
69-72 Wiper Arm Vacuum Relay testing.
Last edited by Willcox Corvette; Mar 13, 2018 at 12:31 PM.
Melting Slicks
Joined: Mar 2005
Posts: 2,093
Likes: 297
From: Midlothian VA
The large actuator (top photo posted by Alan) is easily tested without any tools. Simply remove both hoses, put your finger over one of the hose connectors, then attempt to move the piston rod (easier to do on the bench but can be done in the car by manually raising the wiper door using your hand). If it moves while you have the hose connector covered/plugged then the actuator is bad. If it won't move unless your remove your finger from the hose connector then it's good. It's just a big diaphragm with an opening on either side.
Last edited by Hammerhead Fred; Mar 12, 2018 at 10:31 PM.
