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77 Tachometer Repair

Aug 29, 2001
Norcross, Georgia, United Stat
2017 Arctic White Grand Sport
I am in the process of pulling out my speedometer and tach for repair but can't get the front of the dash on the drivers side out. I have pulled out all the dash screws, the air conditioning duct and the two steering wheel support screws. Everything I have read says the steering wheel should drop but it is not.

:confused Have I overlooked something? I'm concerned about placing too much force on the steering column in my attempts to get the panel out. There is also a collar on the steering column that goes over a part of the panel that covers the steering column and I'm assuming that when the steering column drops, this piece will come out from under the collar.
It should drop at this point. However, you may need to go up to the mounting plate on the firewall and losen those bolts. You will see a plate around the steering column at the firewall with about two bolts in it. That should do the trick and down it comes.
Finally got the steering column to drop. Had to remove the mounting plate on the firewall as well as loosen the first set of bolts on the steering column inside the engine compartment.

I have taken the tach and the speedo to a shop here in the Atlanta area and have started to look around behind the dash. I have never had any air flow to the defroster and now I think I know why. There is a 1/2 inch gap between the defroster ductwork and the defuser below which controls the airflow.

Has anybody seen this before? Is there an adjustment (I couldn't find one), a skirt that goes around this gap or some other way to close this gap?
Got the driver side lower dash panel back in today. Was feeling really proud until I tried to lower the headlights using the vacuum switch under the dash. The darn things won't go down.

Before I screwed everything in place I checked and the headlights went up and down so the system is working and most likely I pulled a vacuum line loose.

Anybody have any hints on checking the various vaccum lines, swithches, etc., without having to pull the lower dash back down. I have seen suggestions on other lines about using smoke from a cigarette, sucking on the lines, etc., and I'm eternally hopeful that someone will have a suggestion. Needless to say I am not very excited about having to take this thing apart again.

I don't know of any other tricks.

Don't feel bad, I have to do everything at least three times until I get it close enough to go back and re do it another three times until it is right.
I've got the dashpad off again. Looked for some obvious crimps, etc. that might affect the vacuum and found nothing.

Can someone help me to understand the vacuum setup for this circuit. I have a line with a tan stripe coming from under the dash to the override switch that raises the headlights. There is a line with a blue strip running from the override switch to the light switch. Then there is a line (has some colored strip but has faded so bad I can't tell) that runs from the light switch toward the firewall (can't tell where it goes at this point).

How does the vacuum run? Through the light switch to the override switch or vice versa. With the car running should there be vacuum at the override swith and/or the light switch. There is none at the override switch with the lights off (I didn't think to turn them on and then check them; nor did I think to pull the vacuum off the light switch and check that).

I'm hoping that this is something simple. The lights went up and down before I put it back together so I'm thinking I either crimped a hose or pulled it off a connector. :mad

Thanks in advance.

Dash is out, vacuum works. Now I need to put it back together.

This side is such a problem, and I need to do it ultimately, so I went ahead and ordered a new lower dash from The Last Detail here in Atlanta. Didn't really have the cash but did not want to have to take this side apart again.

Should have the part in 4 or 5 days.

With any luck she'll be out on the road next weekend for the first time since early September.:beer


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