Hi!

While waiting for my friend to get the bits and bobs needed for his '72 LT-1, another friend and myself did a bit of work on my '71.

Among other things, we had the driver's side dash out to fix the odometer and put new dials in. Went mostly well, but 2 things aren't as they should be:

1. The wiper door doesn't... I discovered this in heavy rain going to said friend's workshop for further work. You can get the door to open using the override switch, but it opens slow. If the wipers are then on, and one pushes the override back in, the door will close when the wipers are switched off....!?!?
BTW., I recently reconned the engine-bay side of the vacuum system for the wiper door with Willcox parts, so I don't think the fault is up front.

2. The trip odometer doesn't engage and turn. We had the speedometer apart and replaced the worn plastic gear and did a general clean & lube. Everything worked fine on the bench with an electric drill as motor, but now fitted to the car only the odometer works.

Any ideas would be very much appreciated!

Cheers

Es

 

Can't say for the wiper door as there are a bunch of things that could affect it

For the trip odometer, if there is any drag on the reset cable it will not let the "cone" slide back to re-engage the gears and let it turn as the miles go by. You can test this if you press up pull down on the reset **** while driving (yeah you need to hold it down for a 1/10 mile or so to see it turn)





If that's the case, and it's the cable rather than something inside the unit itself you can unscrew the cable and try to free it up / grease it more so it slides extra free, the spring in the trip odometer is pretty weak
M

 

If the reset worked on the bench but not installed in the car you probably have the cable jammed between the housing and the dash bracing right behind the housing. The cable is supposed to go beside the bracing but can get caught and bent down if you are not careful and the severe angle of the cable results in the reset not working. I did it on my 69. Twice...
If the wiper door only opens with the under dash overide switch and not normally, check the wiper door relay for correct operation. It's the same relay as the headlights so if you switch them, that would confirm it or you can go to the Willcox site for testing procedures.

 

Hi!
Found the schematic at Willcox'!
What's the solenoid #7 (upper RH corner roughly) do?




Cheers

Es

 

In the diagram, line 7, 8 and the red arrow D in the top right corner connect at the headlight switch on the dash.

 

What's the solenoid with the purple line going to the override switch do?

 

It's what uses the electrical signal from the wiper switch into the vacuum switch to open the wiper door


(Frequently called the tach solenoid just because that's what it's bolted to but has nothing to do with the tach at all of course)
M

 

The solenoid should block vacuum when the wipers are turned on. Are you sure you plugged this back in when you had the dash apart? There is a ton of wiper info on my tech site at this link. http://repairs.willcoxcorvette.com/?yt=1971&s=wiper+

Willcox

 

if door opens with override but not wiper switch id be looking at the tach solenoid. its a pretty simple 12v switch, can be pulled out and bench tested, and even taken apart and cleaned.

 

Thanks guys!
one of the tabs in the solenoid was a bit wobbly, which to me would indicate that this is the culprit....

The more important question is: can it be reached without taking the dash out again?

Cheers

Es

 

Thanks guys!
one of the tabs in the solenoid was a bit wobbly, which to me would indicate that this is the culprit....

The more important question is: can it be reached without taking the dash out again?

Cheers

Es

 

yes. i know a lot of guys take the seat out to reach under the dash easier. but its attached to the bottom rear of the tach, it can be removed and replaced without removing the dash.