C3 - Wiper Door Issues

[Andrew Johnson]

I just purchased a C3 and the wiper door works very well except for two small hiccups.

1. The door sometimes will close before the blades get into the wiper box. Therefore, I have to pull the wiper vacuum lever to get it to reopen and then close it.

2. The wiper box will slowly open after I turn off the car. In about 2-minutes it is about half way open. It stays this way for a few hours until it settles back into a closed position. I should mention that when I start the car it quickly half-way opens and then closes right back. When the car is running it stays in a perfectly closed position.

I look forward to your advice.

Regards,

Andrew

[Jack H.]

Re: C3 - Wiper Door Issues

Classic symptoms of vacuum system leaks, failure to maintain, and improper adjustment of elements. Time to get a copy of Vacuum Troubleshooting (many catalog houses including Dr. Rebuild sell a good pamphlet) and read up on how your vac system works + how to effectively troubleshoot it. Also, suggest you order a spare vac check valve and 1-2 in-line vac filters as these wear out and few prior owners took the time to do periodic maintenance and replace....

Last, get the Chassis Service Manual for your car. It will explain who does what w.r.t. the wiper door and headlights. You'll see it's 'impossible' for the wiper door to close before the wiper arms are properly parked UNLESS someone's jury rigged around the vac switch in the cowl plenum OR the vac switch is improperly adjusted (mounts through enlongaged slots so vac switch can be fine tuned up/down to trigger when the wiper door closes with the knowledge the wiper arms are properly parked in their rest position).

Have fun!!!

[Dick W.]

Re: C3 - Wiper Door Issues

In issue 13-3 of the NCRS Restorer magazine is a very good article on the operation of the wiper door operation. It is listed for the '68 model, but it would be applicable to the '68-72 as far as operation goes.

[Bill Jackson]

Re: C3 - Wiper Door Issues

My 69 would do this since brand new. Once in a while it will do the up/down when starting. As for closing on the blades,it also has done that occaisionally since new. I got in the habit of turning off the wipers as the approached the end of the down stroke. Never a problem doing it that way.