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Okay so though my father gave me the coolest car on the face of the planet, he also gave me something thats bin worked on by people who think they knew what they were doing and alot of stuff that you need to be able to drive doesnt work. The critical ones being the Lack of Speedo/tach/odometer, turn signals, horn, window switches, and wipers. So I'll try and give you guys my ideas as to what could be wrong and see if im close.

The Odometer/Speedo/Tach do not work. This leads me to believe that its something they all have in common. The gauges in the center console all work (oil press, temp, Battery, and whatever the other one is lol). Do the speedo/tach/odometer need electric current to move? and if so are they all on the same fuse or something?

Turn Signals I beleive are the result of a problem in the indicator switch in the column, is there a way to verify this?

The horn i know what caused this... a friend with over zealousness in replacing my ignition cylinder:spanked: (leads me to believe that his replacement of it has caused my turn signals to go kaput)

The Window switches are missing. Period end of sentence:WTF. My father in his infinite wisdom tore apart the interior and left nothing in place. so I need to know what interior parts are missing over the transmission tunnel( I have nothing there... just the shifter) So I have no idea what its supposed to look like in its entirety.

The wipers dont work. I move the switch and nothing happens. I know that the wiper door was actuated by vacuum but that is long gone(well its in my basement) and isnt needed with the L88 Long hood. Are the wipers themselves activated on vacuum or are they electric and have been disconnected like so many other things in this car.

HVAC also doesnt work but that isnt as big of a deal.

The reason Im asking this because to me this stuff is priority because if one of these aspects is missing on a roadside inspection I'll be up the creek. Sorry for asking so much in one post but I figure that some of these could be related.

Thanks for any and all help in advance

-tom
 

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Assuming that neither your speedometor nor your tachometer were converted to electric, they are very basic mechanical devices.

For the speedemeter there will be a cable from back of it that connects to the transmission. It will probably consist of two cables that connect in your engine bay near the firewall. You could disconnect them and hook the cable inside to a drill and test your speedometer to make sure it's working. The cable should look like this: speedometer cable

If it's working, reconnect it. Now you'll need to check the end of the cable that connects to your transmission (is it auto or manual?). If you connect that end cable that goes to the transmission to your drill and the speedo still works, you'll probably need to pull out the speedo driven gear from your transmission and see if it's stripped. It should look like this but may have different colors:
speedometer driven gear

For the tachometer, it's the same cable as above, but only one of them, that connects directly to your distributor. Most likely the distributor drive gear is stripped inside the housing that your cable connects to. There's a distributor cross gear button inside there that was originally plastic that I believe is fairly common for it to break.

I hope that gets you started, I'm sure others with chime in with more detail.
 

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Speedo and tach should be cable driven and I would look at the cable and make sure it is connected to the gauges and the distributor and trans. If not you may need to connect them or replace the cables. Often if people swap to an HEI distributor they leave the tach disconnected.

The horn could be one of the contacts broke or there could be an issue with the horn relay.

The wipers are all electric. If the vacuum door has been removed there could be an issue with the switch the door triggers when it is open. There could also be an issue with the switch or even the wiper motor itself. If you have the time to pull the panel above the center gauges you can see if the switch is hooked up.

If the person pulled the turn signal switch to do the ignition lock that would have been broken or placed in incorrectly. If you check corvette FAQ or Google Jim Shea he has numerous papers on pulling the column apart.

Good luck with the troubleshooting!
 

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...worked on by people who think they knew what they were doing ...
What the previous shade tree mechanics did or did not know is not important. What is important is that you know what you're doing. Purchase the assembly instruction manual (AIM) and GM Chassis Service Manual for your model year. The AIM will show you how the cars were assembled, list the factory parts, and list the original factory part numbers. The chassis service manual will be helpful in making your repairs and troubleshooting.

Purchase a reproduction owner's manual and read through it. There is a lot of valuable information in the owner's manual.

...The Odometer/Speedo/Tach do not work. This leads me to believe that its something they all have in common...
What they have in common are drive cables. Both of yours (speedo and tach) are disconnected or are broken. The odometer is part of the speedometer head. If the speedo is not working, the odometer will not work. Odometers can also die on their own, so you might get the speedo working again and still have an inoperable odometer.

...Turn Signals I beleive are the result of a problem in the indicator switch in the column...
Could also be a blown fuse; poor ground; flasher; or, the turn signal switch.


...The horn i know what caused this...
Could be a bad horn relay; bad horn contact. Could be 40 year old horn wiring. Have you tested the horns?


...The Window switches are missing...
You will need two replacement switches. The AIM shows the installation in the ebrake console.

...My father in his infinite wisdom tore apart the interior and left nothing in place. so I need to know what interior parts are missing over the transmission tunnel( I have nothing there... just the shifter)...
The AIM has assembly diagrams of the interior, including the center console, shifter plate, ventilation controls, etc.

...I have no idea what its supposed to look like in its entirety...
Purchase two or three of the Corvette coffee table books. All of them will have interior pics. Dr. M. F. Dobbins has two C3 guide books showing tons of stock interior photographs for various model years. The first volume covers the 68-72 model years; the second volume has 73-77. They are good reference books.

...The wipers dont work...
Could be a fuse or a relay. Might be the actual switch in the bezel. With the wiper door removed, it is likely to be the wiper switch on the cowl.

...HVAC also doesnt work ...
The ventilation contol in the console trim plate has to be grounded. If your console is gone and if the trim plate is missing, you lost the factory ground for the ventilation controls.

:thumbsup:
 

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Discussion Starter #5
What the previous shade tree mechanics did or did not know is not important.
reference books.
Its not that a shade tree mechanic worked on my car, its WHAT the shade tree mechanic did to my car:thud:. The one who ripped apart the interior was literally a crackhead who ended stealing a lot of stuff from my family including the speakers that were in the Corvette :spanked:. Its a matter of fixing what he broke, which is mainly from what i can tell, wiring... it wasnt my favorite class in college either.

Right now I have the old haynes manual, 1966-1982 Corvette shop manual by motorbooks and a chevrolet service manual for 1977 Vette's,chevelles,camaros,nova's and monte carlo's. I will definately pickup the literature you prescribed, because you can never have to much knowledge. I also have a binder which has a bunch of corvette info in it( a lot of exploded part views but no info).

So you know Im not a complete fool when it comes to mechanics, I trained in it even co-ped @ ford and BMW but counldnt find a job when the big three took a dive.
 

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FWIW: be aware the Haynes is very generic and tries to be a one-size-fits-all. It's handy every now and then, but model year specific reference sources are always better.

The 77 manual may not help a whole lot if you're working on a 69; while a lot of the C3 stayed the same, a lot changed after 69 and through 77.

:thumbsup:
 
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