Instrument cluster rehab....

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My headlight switch came unplugged on my ‘68 300 the other day. To get to it, I removed the Warning light bezel, to get to back side of the cluster bezel that houses the switch. Lights fixed, no problem.

now with the cluster half disassembled, I have decide to go all the way and rehab the whole thing. I am not much of an electrician, but I am going to give it a go. I ordered all the LED bulbs earlier today Based on some posts I read....and installed the solid state voltage regulator under the hood I received a couple of weeks ago.

I searched the best I could and found some good posts on the ammeter bypass which seems like a no brainer to complete. I also found a post on modernizing the voltage regulator on the fuel gauge which might be the solution for my ever bouncing fuel gauge.

Between being a little overconfident and hopefully some sage advice from the C Body crew, I feel this will be a success.

If any of you know of some posts I should read, can you Please cross link them here? I know there has to be more, I just could not find them.

I’ll probably be pulling the instrument panel this week to get a look at the back side. The speedometer has never really worked well in the 20+ years I have had this car. Any advice there is appreciated too.

I look forward to any advice you can share.

94098F18-5451-4772-94FF-38C65B1E59A9.jpeg
 
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I'm doing the same now on my 65, still working on the bulbs I need to order, but I'm freshening everything up. Did the exterior lights and the courtesy lights and they are like the sun compared to 55 year old bulbs. Excited to see your progress, I'm following a similar path, down to touching up the speedo.

PM me any bulb types or posts you found that discuss bulbs options, excited to get this show on the road
 
Been there....done that.
You are on the right track!!
BTW,I find it easier to work on the dash with the front seat out.

To confirm that it IS the speedo,disconnect the cable at the trans and spin it with a cordless drill COUNTERCLOCKWISE
If it works,pinion gear at trans.
If it still no worky,check connection at speedo head or replace the cable (cheap)
boab august 2017 015.JPG
 
Since you are going to pull the cluster....clean the bulb lenses in the cluster .
I usually use q-tips wet and dry.
 
Since you are going to pull the cluster....clean the bulb lenses in the cluster .
I usually use q-tips wet and dry.

Good call. I was debating just replacing them with modern plastic but cleaning will probably be enough
 
Thank you for theses initial thoughts.

BTW,I find it easier to work on the dash with the front seat out.

I can't wait to be upside down under the dash for hours working on bulbs

At 6’7”, I have realized it takes a special kind of yoga to work on the dash.

On the speedo, if the issue is not at the trans pinion or the cable itself, is there a place that rebuilds the mechanism in the cluster? Is this something easily done at home??

bulbs should be here by the end of the week!
 
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Thank you for theses initial thoughts.





At 6’7”, I have realized it takes a special kind of yoga to work on the dash.

On the speedo, if the issue is not at the trans pinion or the cable itself, is there a place the rebuilds the mechanism in the cluster? Is this something easily done at home??

bulbs should be here by the end of the week!
Try locating a good working spare if needed.
They are available NOS on Ebay $$$
Plenty of 67 68 being parted and listed on this forum and FB.
Your original can be rebuilt and calibrated but can be expensive.
Google Mr. Heaterbox. I deal with them on a regular basis since they are local to me and know their Mopars
 
As I continue to think through my rehab project, I am wondering if I’ll need one of those bench top voltage power sources or if some clips to a 12 volt battery will do for testing out the bulbs, gauges, etc, before putting it all back into the dash? Any tips??
 
As I continue to think through my rehab project, I am wondering if I’ll need one of those bench top voltage power sources or if some clips to a 12 volt battery will do for testing out the bulbs, gauges, etc, before putting it all back into the dash? Any tips??
I used an old 2 amp battery charger. Also used an old transformer for a HO train set,LOL
When testing the gauges,do not put full 12 volts directly to them!! power up the voltage limiter which feeds the gauges!!
Even better,I use a multimeter for continuity testing no power needed.
Works best on everything--gauges and bulbs.
 
The order from SuperBrightLEDs came in yesterday. I also found a replica, solid state voltage limiter from Vans Auto that I'll eventually use to rehab the instrument panel, but for now I am going to try and tackle the indicator lamp bezel to build my confidence before trying to takle the gauges and speedo. Let the fun begin!

I bench tested each bulb using a little 9-volt battery and some alligator clips. They are as they claim, SUPER Bright. But unlike the incandescent bulbs i am replacing, the LED bulbs are polarity specific. When I get them into the printed circuit boards on the indicator light bezel, I cannot get them to light up. I definitely want the LEDs for longevity purposes and the lower electrical draw on the system, but I don't know if I am up for re-wiring the whole dash to do what it might take to make it polarity specific. Any one have any luck using these LEDs bulbs? Is it possible to reverse/dedicate the polarity in the bezel??

Thanks in advance!

Dean
 
Body is ground.
Determine on the bulb which terminal is positive and make sure it is matched to the feed.
 
Thank you @cbarge. I’ll keep working this through and keep you all posted.

Switching gear slightly as I turn my focus to the instruments of the 68 300, even though I haven’t pull that out yet.

Ammeter: should the indicator needle be in a resting position to the left when the car is turned off, battery disconnected? My current one is in the middle. My guess is it is toast.

Clock: mine has never worked in the 20+ years I have had this car. I’d love to get it up and running again, but it seems like these clocks are notorious for going bad. Has anyone here sent a clock in for a quartz conversion? I do have a delete plate I can put in its place, but I would probably opt for a dead clock rather than a delete plate. At least it would be the correct time twice a day. Anyway, any clock repair vendors out there?
 
Thank you @cbarge. I’ll keep working this through and keep you all posted.

Switching gear slightly as I turn my focus to the instruments of the 68 300, even though I haven’t pull that out yet.

Ammeter: should the indicator needle be in a resting position to the left when the car is turned off, battery disconnected? My current one is in the middle. My guess is it is toast.

Clock: mine has never worked in the 20+ years I have had this car. I’d love to get it up and running again, but it seems like these clocks are notorious for going bad. Has anyone here sent a clock in for a quartz conversion? I do have a delete plate I can put in its place, but I would probably opt for a dead clock rather than a delete plate. At least it would be the correct time twice a day. Anyway, any clock repair vendors out there?
Ammeter gauge should be resting in the middle.
I got two clocks done with Quartz Movement.
The 67/68 Chrysler clock guts are different than the rest,so the typical quartz converion kits out there will not work.
I had my clocks done by MR.Heaterbox.
Brian Ball and family do show quality work.
Tell em I sent ya!
Welcome — Mr Heaterbox and Interior Restoration Services
 
Thank you @cbarge. I’ll keep working this through and keep you all posted.

Switching gear slightly as I turn my focus to the instruments of the 68 300, even though I haven’t pull that out yet.

Ammeter: should the indicator needle be in a resting position to the left when the car is turned off, battery disconnected? My current one is in the middle. My guess is it is toast.

Clock: mine has never worked in the 20+ years I have had this car. I’d love to get it up and running again, but it seems like these clocks are notorious for going bad. Has anyone here sent a clock in for a quartz conversion? I do have a delete plate I can put in its place, but I would probably opt for a dead clock rather than a delete plate. At least it would be the correct time twice a day. Anyway, any clock repair vendors out there?
I have had the clock ‘quartzed’ in the Rally Pac in my Mustang.
These old clocks used a spring and a set of points to wind up a movement. Often, the points weld shut and/or the movement gums up, causing seizure / failure...
 
I have had the clock ‘quartzed’ in the Rally Pac in my Mustang.

Where did you get this done? @cbarge's guy is in Canada, I would rather not have to deal with customs having to ship out of the country (I am in the US, Norther California).
 
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