I just purchased a '68 convertible to put on the road. Though there are plenty of things to work on, I need to get the wipers working properly to register the car.

If I plug in all the wiper connections under the hood, and flip the switch, the wipers come on. However there is no speed control, and when I turn the switch off the wipers keep going.

Does the switch just need to be replaced? Is that a Napa part or something I have to order from a specialist? This is my first Corvette.

Thanks.

 

Congrats on the purchase, I myself just purchased a 68 convertible early last month (also needs work). My wipers were also an issue but a few hours playing around with the plugs solved it. I have restored a 74 and 78 coupe before and never really had to deal with the wipers much. Your first purchase and best investment besides the car itself must be the "68-82 Assembly Manual" found in Corvette Central for $23.95 Part Number: 113075 (Comes with organized binder). This book is amazing and shows you exactly how the factory put your car together along with wiring diagrams. Order this pronto so you can chase down any imperfections with the car, especially the wiper system. 68 is the first year for the new body style and a first for many other things including but not limited to the wiper door system and door locks. You won't find the door locks on any other corvette, probably b/c they caused more harm then good so if you ever lose the key or they break you will have to take them to a locksmith to have a key matched or locks rebuilt. Won't find them in any catalogues on earth. I would look up some wiring diagrams for the wiper motor and switch on the internet while your waiting for the assembly manual. Check all the switches, make sure there is no short in the system and it is grounded. It may very well be the actual switch that is "stuck" in the open position or wires may be crossed. All of these parts cannot be found at the local hardware store, your best bet is to order them from a reputable corvette parts catalogue that comes with a standard warantee. Corvette Central, Mid American Motorworks, Corvette America, ect.
I just fixed the door locks, wipers, rear convertible hatch and will be replacing the body mounts, convertible top and sprucing up the engine compartment where a 454 lives. I have a lot of plans for this beauty so keep in touch and we can help eachother out. Good luck with the wipers.

 

The switch is probably a good place to start. It is easy to get to and you can easily check it out with a multimeter. Remember also that there is an override switch under the steering column...maybe you can pass the test by turning them off with that switch.

 

Thanks. I will order the manual.

I did not know about the override switch under the dash. I will check it out and reply back.

 

The over-ride switch works fine, and I think I can get it past inspection using it. Thanks.

I still want to get the wiper switch working properly however. I'll scan the web for a good wiring diagram until the manual come in.

 

Try Corvettefaq:

http://wiki.corvettefaq.com/index.ph...e=Misc_Overall

This site has two articles specific to the '68 wiper system with diagrams

 

It's also possible that you have an incorrect replacement wiper motor.

The 68 had a unique switch/motor combo.
It is wired different than other C3's.
I've run across incorrect wiper motors installed, which in turn damaged the wiring and/or switch.

For example: Paragon lists 4 different wiper motors:
#3888 68
#3889 69-72
#3890 73
#3884 74-82

They list only one wiper switch: #5625 68-76, BUT...

there was a difference in the way the switch was mounted in 68 which resulted in a different grounding scheme. So it was possible to burn out the components/wiring with the wrong motor.

I worked on a 68 for 3 days once only to find this out. Bubba had rigged the wiring to try to get a wrong motor to work and it fried the wiring & switch. I had my own 70 and a 72 to compare the switch install/design.

 

I had some of the same problems on my 71, going from fixing the vacuum to then finding the electrical problems. I found a manual from Speed Hound Performance that covers just diagnois of the wiper system and all the componets that go with it. Anyway it helped me.

 

All great advice, thank you.

I went to the website with diagrams and it is great. Very nice trouble shooting flow chart. According to it, the problem is a defective motor relay. It says the relay is somewhere on the right side of the console, but I have not found it yet.

I am going to check the wiper motor for a part number to see if it is correct. That would really be a pisser if the wrong motor is the cause of all this.

 

Well the flow chart said it was a bad motor relay. I replaced the relay under the right side of the console, and it did not fix it.

BTW, the guys at O'Riley's matched up the part, and the relay is still available as a blower control relay, BWD R365, for $12.99. Or I just replaced the wrong relay.

Does someone know where the wiper motor relay is located? I need the assembly manual to show up.

Also, I could not find a part number on the wiper motor, but it is definately a replacement.

Thanks.

 

My 68 that I purchased in 1974 had a terrible problem. Apparently the motor would spontaneously turn itself on, say in the middle of the night. Since the vacuum was zero, the wiper doors would of course not open. The wiper would advace the blades from the "stored" to the "run" position where they would contact the closed wiper door and then in a jammed position, draw current and discharge the battery. Since this was an intermittent,random condition I was never able to fully substantiate what was happening, and of course, never found the real cause of the problem.

I normally kept my 68 wipers disconnected, except when caught in rain, I pulled over to the side of the road and connected them. PITA.

In the early 80's I decided to change out the 68 wipers to a 69 wiper configuration.....This was much more difficult than I anticipated but...I did solve my problem. Wiper bliss.

To day, restoring my 68, I've since had my original wiper motor restored and hopefully this will have solved the problem. Also, I've installed a new 68 engine harness to correct changes I made to the original harness. With an all new 68 configuration, maybe the thing will work. Or maybe I'll once again have to leave the68 motor disconnected!!!!!!!

I think one of the problems with the 68 motor,..this is something I read on this forum recently,...is that the 68 motor windings are continuously energized by the battery. All they need to start running is a ground connection. If something intermitently causes a short condition, the motor tries to run. I haven't checked to verify this "hot winding" story, but it sounds reasonable.

 

Here's a thread on the switch. I debugged my issue with the 71 wipers, it was the switch. BTW: I did a complete replacement on the vacuum hoses before I tackled the w/wiper switch...

http://forums.corvetteforum.com/show....php?t=1285231

 

I tried "grounding" the switch, but no luck, the wipers keep running.

Removing the switch completely does not stop the wipers from running (I turn them on and off by disconnecting the motor wires). The wipers just will not park.

One site said it was the wiper motor relay. Where is that relay?

Thanks.

 

If it's like my 69, the relay is under the shift console, up near the ashtray. You have to remove the shift console to get to it. Looks like an old horn relay.

Here's a pic of the "826" wiper relay. BUT...REMEMBER, as others have said, 68's are wired differently SO your 68 might use a different relay. Check your Assembly Manual. Chuck

 

Thanks. That is what one of the sites said as well. I replaced that relay with a new one (now a heater relay has the same charactoristics), but it did not help. So I was thinking I had the wrong relay. Bummer. Now I am stuck.

 

You can get a correct '68 wiper motor from Auto Zone. I had issues where my door was always up (bad park switch in the motor). Once I replaced the motor, everything was perfect. Sounds like something in the motor failed. The wiring gets a little goofy inside the motor. I think I only paid $45 for the new one, with no core charge.

Good luck.

~Rich

 

Autozone.... off the web...

CARDONE_REMAN WIPER MOTOR for a 1968 CHEVROLET CORVETTE

Unit Price: $54.99
Core Value*: $10.00
Part No.: 40-146
Weight: 4.5 lbs.
Warranty: LLT
Availability: Online: Special Order
Store: Special Order

 

Years ago (like 20 years ago) when I had a problem with my 68 wiper motor I bought a rebuild kit from the Chevy dealer. I can't remember all the parts it included but it had the internal wiring for the motor. You might check it out.