Windshield wiper function
 

When I bought my '68 couple built 1/8/68 so late model, it had a windshield wiper motor but no washer or cover. The gear housing was broken but when wired direct the wipers would work. I couldn't figure out how to get them to colapse though. I bought a new/rebuilt motor with washer and installed. All wiring matches '68 assy wiring diagram. Vacuum system works. Wiper door works and override switch works. It has a new wiper switch in dash. I can hear the switch in the console click when I turn on the dash switch. I'm not sure about the vacuum switch under the dash that mounts to the back of the speedo. I have tried testing it by connecting power to it but I don't get a signal that anything happens.

When I turned on the new wiper motor nothing happened so I started the car to activate the vacuum system ( I had the wiper door open before). Nothing happened. While I was in the driver's seat trying different things, the ground wires fried as did the leads to the wiper motor, and the connectors the wiper plugs into the firewall wiring haness. I have repaired or replaced the fried wires but not the firewall connectors. Any suggestions as to what went wrong? How can I wire the motor direct to make sure it works and get the wipers to colapse when I deactivate it? I know the system is complex but would like the satisfaction from figuring it out and getting it to work. I know that someplace I had power to ground connected but I follow the schematic and relied on some of the car being correct to start with. Thanks.

Larry
740.816.1344

I'm not sure about the 68, but later years had a black ground wire that connects to the body of the wiper motor. The other end of that wire is supposed to connect to one of the bell housing bolts for ground. Commonly that wire gets mis-connected to the battery connection at the starter and causes problems. That is the first thing I would check.

This document from Willcox is the only one I've found that addresses the 68.

http://willcoxcorvette.com/repairand...lp.php?hID=201

68,

Other things on the site for your car that might help you are:

Corvette Windshield Wiper Diagnostic Help 1968 http://willcoxcorvette.com/repairand...lp.php?hID=195

And

Corvette Headlamp and Windshield Wiper Vacuum Small Parts, How They Operate!
http://willcoxcorvette.com/repairand...lp.php?hID=218

Willcox

Thanks. The schematic shows that wire as a ground but my car doesn't have that wire and the wiper housing is already grounded. The wiring schematic was created at the beginning of the year. My car was built on 1/8/68 and is considered a late '68 so they may have dropped that wire or over the past 41 years someone eliminated it but I can see no value in adding it and it's absence doesn't seem to be my problem. Somewhere though I have power to ground. Your suggestion was a good one. Thanks again.

This is great. Thanks

Larry

Wilcox, this is great. I read through it briefly. I've been dying for this info. For a hobby, I am pretty technical. Thsi has really had me stumped. I'll get in touch with you when I need parts. I really appreciate your help. I stopped working on it last July after I fried the wires. Probably won't have time to get back into it for a couple more months.

Larry

Thank you Larry,

The schematic for the 68 is dead on too! All the factory schematics have the wire colors wrong and even show a wire changing color at the firewall.

Since 68 is the only wiper motor that functions in a different way than the 63-67 and the 69-82 cars you have to have everything right for it to work. You probably know more about this than I do now, it's been about a year since I did these pages.

The 68 test info is something that I don't think you find posted anywhere else. We used a original motor to creat this and it took some time but it was well worth it.

Once done, we then duplicated the wires in our test machine here (Frankenmeter) so now all we have to do is plug up the motor to test.

Good luck,

Willcox Inc.

I'm a newbie and I hope i'm sending this message to Willcox.

You folks are the greatest and I doubt many guys can REALLY appreciate the assistance that you folks provide. I printed and studied every tip I could find from you and by gosh it lead me to success!! Thank You Thank You!!!!

My wipers are running and wired correctly (limit switch and service switch in series with the ground.) However my dash switch works backwards.

You're the greatest!!!

Jon Slomover Mullaney