The Stovebolt Site Forums The Shop Area General Truck Talk vacuum wiper motors

Same '37 truck..... Need wiper motors re-built. Found detailed instructions on web. Should I try to repair first, then send out for $100 rebuild or just go ahead and send out first?

I would just send it out. Or if you think you may actually need wipers one day get an electric motor. The vacuum wipers were OK in their day, but there is a reason they aren't used any more. And unless you are completely set on originality, this is a safety item in my opinion. That being said, I try and try not to drive my truck in the rain period, but as I live in Seattle, you can imagine how that is working for me. (also why I have electric wipers.) You can use the dual diaphragm fuel pump and vacuum canisters if you like, and get decent performance. I did for many years, but the electric is so much extremely nicer. (at least for me)

If you go the route of rebuiding the vacuum wiper you are way ahead to send it out. Parts are almost non existent so you will need to be prepared to cut your own gaskets.

I understand the electric wipers are not as compact as the vacuum wipers and extend into the cab more. True?

I guess I could send the wipers out in a box of parts. The gasket situation seems somewhat an insurmountable problem.

There are certain parts that can't be revived by a cleaning. Having said that I recently bought an NOS motor for my 38 Master. I tested it out on the bench and discovered that it worked but failed to switch directions. The little valve on the side was hanging up where the shaft turns. After lubricating it the motor worked perfectly.

A couple of easy steps to try before sending yours out for a rebuild. Often what is wrong is the lubrication has dried up and hardened and/or the seal has dried out. First make sure the motor armature is moving if you haven't already by grabbing both arms and gently moving them a cycle or two. If it moves OK put the switch in the OFF position, pull the vacuum hose free of the manifold. Make sure the hose is in good condition (no splits). With the end free from the manifold squirt some WD40 down the hose and work the arms a few cycles. This should pull the WD40 into the housing and soften the lubrication. Once the armature is moving freely pour some brake fluid in the hose and work the arms a number of times. If the seal is only dried out this will soften it and allow it to seal again. The brake fluid won't harm the rubber hose but don't spill any on your paint! If you're lucky you'll have wipers working as well as new. I'm not the originator of this idea but a number of folks have tried it and it often works to rehabilitate "dead" vacuum wiper motors.

You could try this I've done three in the last few years and they are all still working,the one on my 52 has been working for three years now.Good Luck.

http://s559.photobucket.com/albums/ss39/sparky52/trico%20cleaning/

Pete

I have both wiper motors off the truck. I will try the WD40 and brake fluid method before sending them out for re-build. Thanks

moving along....I installed the wind-lace on the passenger door. I used the plan forwarded concerning installing it under the door panel and under the leading window metal. Works great, but now the door has to be shut with some force to get it to completely close. I am thinking I should pull the wind-lace out a little bit on the leading edge of the door to allow a little flexibility in closing against the wind-lace. Good idea?

i bought new electric wiper motors from american classic truck parts.com and they fit up in the same space that my vacuum ones did, but I did run power to them yet because they are 12 volt

David, there is a Door forum where this should be asked.

99% of the time issues with vacuum motors are not the motors, but that the arms and blades. My 66 M35A2 had vacuum wipers and worked great one I replaced the straight arms and blades with spring loaded ones.

Be VERY CAREFUL about shooting goo into the vacuum motor. I'd clean it and lube it properly with light machine oil (3 in 1 is a good type, or sewing machine oil) as this does not gum up over time.

The pot metal housings do have wear points, and they can leak causing poor operation.