So, now that the Chevelle is on the road, I get to dig into some of the other 'issues' I need to take care of.
I have the SS gauge dash and only the Temp, Gas, Fuel, and Speedo work. The Amp gauge pegs to the bottom of the gauge, and when I hooked up the tach (with a square wave filter) it bottoms out too.
When I turn the headlights on, the turn signal indicator bulbs in the dash are dimly lit but the outside lights function correctly.
Finally, almost all the dash lights are out when the park lights or headlights are turned on.
I'm guessing there are some grounding issues in the dash itself? I will start by replacing the dash light bulbs and see what happens from there.
Any other suggestions or experiences you can share regarding dash grounding?
Bowtieman427 said
Apr 23, 2011
Clean contacts to bare metal put di grease in reassmeble make sure you have good metal to metal contacts and wire in more gorunds if needed. Can never have enough grounds. Hook headlights hi and lo to relays get them out of the interier electircal system. If bulbs are working I would check there contacts they may be dirty. Do you have good ground straps from engine to firewall ?
SShink said
Apr 23, 2011
Bowtieman427 wrote:
Clean contacts to bare metal put di grease in reassmeble make sure you have good metal to metal contacts and wire in more gorunds if needed. Can never have enough grounds. Hook headlights hi and lo to relays get them out of the interier electircal system. If bulbs are working I would check there contacts they may be dirty. Do you have good ground straps from engine to firewall ?
Affirmative on the ground straps. There is one from the passenger side engine/valve cover to the fire wall, and one from the transmission housing to the firewall. That's where they were before I pulled and reinstalled the engine.
bowtie said
Apr 23, 2011
I think mine had 2 ground wires when I swapped dashes. 1 went from back of dash to the ebrake pedal. Other I think went to column mount or something like that.
Chris R said
Apr 23, 2011
90% of the time, its that nearly 40 year old printed circuit board behind the dash thats the issue with those style dashes. Seems every person I have ever talked to that had issues with thier original gauge style dash, it was the aged and brittle circuit board that was the problem. Often times, the wiring is hacked over all those years, but even on survivors, they still needed attention.
SShink said
Apr 23, 2011
Well, started getting into the dash and then buttoned it back up for a project in the near future.
Found that someone's been playing with the circuit board. They tried to solder/electrical tape the ciruit plus they disconnected the Amp gauge flex circuit...:
I will put this off for when I can pull the whole dash (Dashboard gave me a copy of the factory service section on this!) as I need to clean up the lenses, paint the silver trim, and then I'll probably replace the flex circuit board at the same time and start out fresh. The good news is that the wiring harness looks really good with no nasty surprises.
All the signals, headlights, tail lights work now but just no dash lights. I can live with that for a short time until I pull the dash. I've learned to pick my battles and stop when I'm ahead rather than tear it apart and then not drive it all...
67ss said
Apr 23, 2011
I would get rid of the amp gauge and convert it to a volt or oil pressure gauge. Check out this link. Scroll about half way down the page.
When I worked on Mikes 72 I found out you need all of those bayonet connectors in the dash with bulbs. The PC film is prone to breaking in many spots I saw and with all of the work to pull reinstall and all that I stuck in a new wire harness along with it. I do not envy you and this job it is slow and tedious looking for that needle in the hay stack.
Bowtieman427 said
Apr 23, 2011
Sorry to hear it was not a simple fix : (
SShink said
Apr 24, 2011
Bowtieman427 wrote:
Sorry to hear it was not a simple fix : (
No worries. I think most of us that are into old cars appreciate the challenge and sometimes figuring out the problem is more than half the fun!
Besides, I've been teased about selling this Chevelle already now that it's in running condition. The dash gives me something else to work on and not have bad 'selling' thoughts!
bowtie said
Apr 24, 2011
There is a trick to pulling the dash cluster out without removing the whole assembly. You'll have to search TC, but it involves using threaded rod to support the carrier being removed far enough to get the gauge section out. Personally, I wouldn't do it. Aside from the bulk, it's actually pretty easy to remove the whole assy, theres about 6 bolts plus a couple wires.
SShink said
Apr 24, 2011
bowtie wrote:
There is a trick to pulling the dash cluster out without removing the whole assembly. You'll have to search TC, but it involves using threaded rod to support the carrier being removed far enough to get the gauge section out. Personally, I wouldn't do it. Aside from the bulk, it's actually pretty easy to remove the whole assy, theres about 6 bolts plus a couple wires.
Yep, that's the one I referred to that Dashboard gave me (maybe that's why he has that forum name?). It's from an old GM service manual. I made copies of the original that he has.
Dave Seitz said
Apr 24, 2011
Bryan once the dash is out the heat duct tubes are rotted and cracked and all sorts of other little things come to light. Again ask me how I know this.
Chris R said
Apr 24, 2011
Yup. Your opening a big can of worms when you pull a dash right when the season starts. Just make sure the wiring isnt all burnt and crispy to the point where you could have an electrical fire waiting to happen under there.
SShink said
Apr 24, 2011
Chris R wrote:
Yup. Your opening a big can of worms when you pull a dash right when the season starts. Just make sure the wiring isnt all burnt and crispy to the point where you could have an electrical fire waiting to happen under there.
Nope, I was surprised how nicely wrapped and flexible it was. I'm thinking somebody replaced it 10 years ago when it was last restored.
bowtie said
Apr 24, 2011
mine weren't
Chris R said
Apr 25, 2011
Neither was mine. Most people dont want to mess with wiring after they restore a car and will leave the stock wiring alone because they are scared of it.
Pushrod said
Apr 26, 2011
hey stan, if you pull the dash assy. one word of advise, and im sure you know this but remove the fuse box, dash harness, and dash as a unit. then you can inspect wiring as its hooked to componants and or replace as needed.
dashboard said
Apr 26, 2011
Stan,
Here's a quick fix for your dash lighting, it should get ya through to next winter when you can work on it.
-- Edited by dashboard on Tuesday 26th of April 2011 01:34:56 PM
Chris R said
Apr 26, 2011
And make sure you get us pictures with that on your head.
For the record. I actually have one of those. I never really use it because I always forget I have it until after the job is done.
bowtie said
Apr 26, 2011
I have something that fits on the brim of your hat. works well if your hat is on and pointed at where you're looking.
So, now that the Chevelle is on the road, I get to dig into some of the other 'issues' I need to take care of.
I have the SS gauge dash and only the Temp, Gas, Fuel, and Speedo work. The Amp gauge pegs to the bottom of the gauge, and when I hooked up the tach (with a square wave filter) it bottoms out too.
When I turn the headlights on, the turn signal indicator bulbs in the dash are dimly lit but the outside lights function correctly.
Finally, almost all the dash lights are out when the park lights or headlights are turned on.
I'm guessing there are some grounding issues in the dash itself? I will start by replacing the dash light bulbs and see what happens from there.
Any other suggestions or experiences you can share regarding dash grounding?
Affirmative on the ground straps. There is one from the passenger side engine/valve cover to the fire wall, and one from the transmission housing to the firewall. That's where they were before I pulled and reinstalled the engine.
90% of the time, its that nearly 40 year old printed circuit board behind the dash thats the issue with those style dashes. Seems every person I have ever talked to that had issues with thier original gauge style dash, it was the aged and brittle circuit board that was the problem. Often times, the wiring is hacked over all those years, but even on survivors, they still needed attention.
Well, started getting into the dash and then buttoned it back up for a project in the near future.
Found that someone's been playing with the circuit board. They tried to solder/electrical tape the ciruit plus they disconnected the Amp gauge flex circuit...:
I will put this off for when I can pull the whole dash (Dashboard gave me a copy of the factory service section on this!) as I need to clean up the lenses, paint the silver trim, and then I'll probably replace the flex circuit board at the same time and start out fresh. The good news is that the wiring harness looks really good with no nasty surprises.
All the signals, headlights, tail lights work now but just no dash lights. I can live with that for a short time until I pull the dash. I've learned to pick my battles and stop when I'm ahead rather than tear it apart and then not drive it all...
I would get rid of the amp gauge and convert it to a volt or oil pressure gauge. Check out this link. Scroll about half way down the page.
http://www.tachman.com/gm.htm
No worries. I think most of us that are into old cars appreciate the challenge and sometimes figuring out the problem is more than half the fun!
Besides, I've been teased about selling this Chevelle already now that it's in running condition. The dash gives me something else to work on and not have bad 'selling' thoughts!
Yep, that's the one I referred to that Dashboard gave me (maybe that's why he has that forum name?). It's from an old GM service manual. I made copies of the original that he has.
Yup. Your opening a big can of worms when you pull a dash right when the season starts. Just make sure the wiring isnt all burnt and crispy to the point where you could have an electrical fire waiting to happen under there.
Nope, I was surprised how nicely wrapped and flexible it was. I'm thinking somebody replaced it 10 years ago when it was last restored.
mine weren't
Neither was mine. Most people dont want to mess with wiring after they restore a car and will leave the stock wiring alone because they are scared of it.
hey stan, if you pull the dash assy. one word of advise, and im sure you know this but remove the fuse box, dash harness, and dash as a unit. then you can inspect wiring as its hooked to componants and or replace as needed.
Stan,
Here's a quick fix for your dash lighting, it should get ya through to next winter when you can work on it.
-- Edited by dashboard on Tuesday 26th of April 2011 01:34:56 PM
And make sure you get us pictures with that on your head.
For the record. I actually have one of those. I never really use it because I always forget I have it until after the job is done.