1970 Dart Cluster Removal

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New Baltimore MI
Hi everyone,
New guy here. We acquired a 1970 4 door Dart Custom. Slant six three on the tree. Vehicle has been sitting since 1993. We got it running, stopping and driving. Now on to the gauges. New fuel tank and sending unit. The gauge kinda works; 5 gallons of gas in the tank, and the needle moves a little. The temp gauge doesn't work at all.
Anyway, I know this has been covered dozens of times, but I cannot get the instrument cluster out. I have the speedo cable removed. It looks like the heater bezel has to come out first, but I cannot see how to get it out. I see horror stories about the pins breaking on the cluster where the wires connect, and I don't want that either. What am I missing? I cannot seem to even get it to the point where the steering column is in the way!
Any help is appreciated.

Tim
 
Remove the Speedo cable, remove top and bottom screws holding the cluster to the dash. Unbolt the column from the firewall. Remove the lower column cover/dash trim. Unbolt the column and let it lay on the seat. I always leave it connected to the steering box. The dash wiring harness lays across the back of the cluster and sometimes gets caught up on the Speedo housing, so just reach up from the bottom and pull it out of the way if necessary. The cluster will pull away from the dash and roll out to expose the wiring connectors. There is a light socket on the left side of the cluster for the park brake indicator. Carefully remove the wiring connectors and pull the cluster out.

It's been a couple years since I have had mine out for repairs. But I had to pull it a couple times to get it all working. Do yourself a favor and buy a new voltage regulator for the gauges.
RTE limiter - rte
 
I just did this last week! All the stuff above is correct, but I'll add a bunch. I'll refer to the speedo gauge unit at "the unit". Disconnect the battery!!! If you have a cheapo steering wheel puller, pulling the wheel lets the column drop down much lower to ease removal of the unit. The unit bottom is lower than the metal dash opening so when it come out you have to roll the unit toward you Down from the top. Given this, unless you want to trash the plastic cover on the unit, the headlight and wiper switch knobs need to get out of the way. The headlight knob is held in place by the switch and you have to reach up under the dash to the switch and press and hold a small silver button on the top of the switch which releases the knob and stem and you can just pull it out. When you are done, one of the last things to do just shove the knob and stem back in and it will click in place. On the wiper side, pull off the chrome knob (it's just pressed on) and then rotate the chrome bezel on the dash counter clockwise and it screws out of the switch, then you can push the stem and switch back into the dash but don't lose the stem so its easy to pull back through. You should be able to reach the two sets of multi pin connectors pushed into the back of the unit from underneath the dash. Pull them straight away from the unit with slow even pressure. There are two big wires with ring fittings that run through the alternator gauge (these are the main reason you disconnected the battery since they are the main power wires to almost everything in your car). Take off the nuts and remember (write down) which side the red wire is on (toward the drivers or passenger side). It is not good to hook them up backwards. Above it was mentioned that the main wiring harness makes it hard to get the unit out, that is partially because there is a metal clip on the back of the unit that attaches to a white plastic clip that is taped into the wiring harness. It is right below or above (can't remember) the speedo cable connection. There is no reason to ever connect this clip again, so break the plastic piece off the metal clip and don't look back. Now if you care about the plastic unit bezel and the paint on the dash, the unit should be loose enough to stick a thin rag under the unit that covers the paint. Now roll the unit out. If the piece that bridges between the dash unit to the heater/radio cover is stuck under the heater cover try to wiggle the dash unit to slide that piece out from under the heater cover by pulling the dash unit toward the drivers door. Don't follow just these directions and miss what is in the previous post.
If you haven't taken stuff apart yet teat the dash lights because it is way easier to replace them when the unit is out! There is a rectangular aluminum box plugged into the back of the unit and a little round condenser. This a the gauge voltage limiter. Yours is 49 years old. I would really suggest that you buy a modern transistorized unit to replace it. Just pull the old one out and push the new one in which also eliminates the round condenser. Year One, Classic Industries, etc. This will protect all of your gauges from a voltage surge frying them. If you have questions or need parts PM me and I'll be glad to help. Good Luck!!!
 
Three last things... you did try replacing the temp sending unit first right? Taking this unit out is a ***** and you should really have tried everything else first. On the fuel gauge side an easily missed piece is that the sending unit in the tank is grounded to the metal fuel line, but they are separated by a little piece of rubber fuel hose so there is a flat metal strip that clips to the metal line out of the sending unit, bridges over the rubber hose and clips to the metal fuel line. Also after reading your post again, if that voltage limiter is trash, it would effect both the fuel and temp gauges.
 
Thanks for your help. I did manage to get the cluster out. I already knew the sending units were OK. Grounding the wires made no difference. After I removed the cluster, I found two problems. First, the voltage limiter pulses, but very very erratically. I suspect that would explain the crummy fuel gauge readings. The second problem is that there is a break (I cannot see it) in the printed circuit board between the voltage limiter signal from the fuel gauge to the temp gauge. I made a jumper, grounded the gauge on the bench, and all is well there. Now, I'm going to build a new voltage limiter using a 7805 solid state regulator, and all will be well.

Thanks,
Tim
1970 Dart slant six three on the tree sitting since 1993
1964 Dodge A-100 Custom sportsman
 
The homemade 7805 based regulator will work but... fuel gauge needle at switch on will be slow as molasses, both gauges may read a tiny bit off. I said may because all 7805 regulators ( and heatsinks ) are not equal. The hotter they get the more voltage they pass. One might start at 4.8X and climb to 5.2X as it heats up, while another brand/lot starts at 5.0X and climbs to 5.5X as it heats up. Anyway...
RTE builds the closest to OEM operation in solid state replacement.
And just so you know, you most definitely need a dedicated ground wire for homemade. The 7805 alone does not have ground fault sense. It will pass 12 volts to/through the gauges if it isn't grounded. Test to prove this on your workbench if you want.
Just another way the RTE package is better. They include ground fault protection in their circuitry.
 
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The break in your circuit board is probably a bad connection from the gauge to the board. I had to remove the nuts, clean them and the board and that fixed part of my problem.
 
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