vacuum wipers
 

I have a '41 Ford and my wipers do not work. I have check vacuum with no good results. How would I go about checking for my problem ? Thanks Terry

Re: vacuum wipers
 

First you have to have a good running engine that makes good vacuum, you should have full engine vacuum present at wiper motor. You might want to watch Mart's video.
https://youtu.be/edfvfb78Tag

Re: vacuum wipers
 

Car or truck ? Ill tell you how i doit for a car . Remove wiper arms and blades .
Remove the three vacuum lines from the switch . Take the large vacuum line from the engine and splice it to the large vacuum line going to the motor . Use any hard tube thatll fit into the hoses . Brass , plastic , fish tank air line connector, hard tube from inside spray windex bottles etc . It should at least try to move with the motor running and having vacuum of +14 in merc . If not its time to remove the vacuum motor . One thing I forgot before you do , make sure the wiper motor interior connectors are not binding on anything, radio , wires etc.
if you have a factory radio its better and easier to remove the radio before you remove the vacuum motor . I found nos motors on ebay but i was able to clean and lube mine and clean and lube the vacuum switch . The switch has a wiper that needs oil or lube to help seal from leaking . They are a very simple set up .

Re: vacuum wipers
 

I have no idea where you checked for vacuum but the banjo fitting under the carburetor on the side of the intake manifold is the source of vacuum that banjo fitting also supplies vacuum to the distributor vacuum brake, through the steel tube. Check for vacuum at that location.

Re: vacuum wipers
 

I was using a hand held vacuum pump to check for any leaks or to get vacuum to move the wiper. Don't know is the switch is at fault or the wiper unit its self. Just want to know how the test the parts of the system.

Re: vacuum wipers
 

Connect the wiper moor directly to the vacuum source and try it. If that does not work the wipers then it's the motor.



If it's the motor, it may be the paddle inside has dried up. One way to soften it up is by using regular brake fluid (not sure synthetic will work). Pour some fluid into a can, put the vacuum hose into the fluid and work the wipers back an forth so the fluid is sucked into the motor. Let sit overnight and then try the wipers. If this doesn't work, then it my be time for a rebuild. As usual, be careful about spilling the brake fluid. Put some rags or other material under the motor just to be sure there are no drips on the carpets. It helps if you have some one to help moving the wiper back and forth. Other people use ATF, I always used brake fluid

Re: vacuum wipers
 

put the vacuum pump on the switch at the large line from the motor, cap off the other lines, move the switch and it should hold the vacuum if the switch is not leaking thru the positions. my 41 the vacuum motor was stuck internally, soaking now.