Replacing 70 speedometer, not as easy.... [Archive] - Chevelle Tech

: Replacing 70 speedometer, not as easy....


no1dc
Jan 9th, 06, 12:03 PM
as I thought. Initially I thought all we's needed to do was remove the dash pad, NOT!!!! What we ended up having to do, especially so as not to break anything(we did, the mounting holes for the bracket on the passenger side) was removing the six bolts(7/16") holding the dash to the body(two at each end, one behind the glove box and behind the A/C duct work and another about center on top. When you pull the dash out BE CAREFUL as 30+ year old plasic is brittle and mounting points can break easily. We also dropped the steering column(9/16") which meant taking off the carpet cover(3/8") to avoid breaking it as well as the lower steering column cover and the drivers side A/C ductwork. Once that was loose the fun began. There are a million 1/4" screws that need to be removed(well only 10 or so but it seemed like a million in those tight quarters). Two on each side, four across the top on back and two at the bottom in the steering column area, they are tricky to get to and if missed you'll break that mounting point. Once things were loose we were then able to pull the speedometer and dash assembly forward to disconnect the cable from the housing. Once it was disconnected we were able to pull the speedometer out. Good time to get the shop vac out and vacuum this area out. In all it took about 3 hours to swap the speedometers out. Found out what "killed" the original speedometer, BLACK MAGIC. No not the voodo kind the media blasting kind. Evidently when they sandblasted on the car they didn't protect this area well enough and that stuff got everywhere, and I mean everywhere. Even though we vacuumed and cleaned before this speedometer swap the first few times we turned the rear defroster on or the front blower on there was black magic flying out everywhere. Thought I'd post for future reference if anyone needs to do this. Not a hard or terribly hard job just time consuming if done right and trying not to break anything. Pete

thunderstruck507
Jan 9th, 06, 3:08 PM
Been there done that...did an SS gauge swap, speedometer didn't work and tach was busted, pulled the dash back out for a new one, ordered tach

put in new speedo...or so i thought, we disassembled both and the faulty part ended up in the extra speedo, went for a drive and got REALLY angry, dropped dash again and put in fixed speedo, odometer stopped working

month or so later tach arrived, dropped dash to put it in and fix odometer, speedo cable wouldn't engage onto cluster for 2 hours, went to bed...got up the next day, barely touched the cable and it popped on

I HATE DROPPING THAT DASH

Jim Mac
Jan 9th, 06, 10:13 PM
when I got my chevelle it didn't have a dash at all, I got a complete dash out of my 72 parts car and installed it, a week later I meet a guy parting a 70 4 door and decide the green numbers would be more correct, so I change it, then the same guy gets a monte carlo and calls me to see if I could use anything out of it and I get the dash, so back out comes the dash and in goes the monte dash. I got real good at swapping dashes that month. Jim

GRN69CHV
Jan 10th, 06, 6:22 AM
I intend to pull mine soon for a good cleaning/detail. I'm right with you