Joined: Sun Oct 16 2005, 01:22PM
Location: Nashville TN.
Posts: 10
I've had this problem for a while and after opening up the dash today I figured it could be a few things so I thought I'd see what other people thought before I dived in. I have four gauges in the cluster. Fuel, temp, oil pressure, and amp. The only gauges that ever worked was the temp and fuel but they didn't work very well. The temp tends to read hot and when I use the head lights both the gas and the temp tend to rise slightly. The back of the amp gauge is slightly melted ( I've read about how this can happen) and the oil pressure just doesn't work but I have replaced the sending unit and I must have oil pressure because I've been driving it without a problem. I've read the articule here (www.allpar.com/history/mopar/electrical2.html) about replacing the electro machanical valtage regulator with a elctronic chip but that was a curcuit board type gauge cluster and after looking at my cluster I'm not sure if I can do that repair. So I'm guessing that I either need to start replacing the gauges or I could have a bad connection at the firewall and if that the case I should probably run some new wires. Thanks.
Joined: Sat Dec 10 2005, 04:28PM
Location: United States
Posts: 4954
Hello Jamie
OK I read this one right.
Let's start with the oil gauge. Ground the wire at the oil sending unit and see if the gauge goes to full.
On the rest of the gauges, try to run a ground wire from the cluster body to the dash. I want to see if it may be a poor ground problem. Also, and here we go again, pull the connectors off on the engine side on the bulk head connector. That is on the drivers side where the wires go through the fire wall. If I remember, there are three of them. Make sure they are clean and free of corrosion. Put some vasoline on the connections and replace them. Make sure they are clipped in tight. See how the gauges respond then and get back to us.
Joined: Sun Oct 16 2005, 01:22PM
Location: Nashville TN.
Posts: 10
Ok. I grounded the oil gauge and it went full. I also ran the ground wire from the cluster body to the dash. I started the car and let it warm up and the temp gauge ran alot more normal if not a little on the cold side. The gas gauge was reading lower as well. The gas and temp are still moving back and forth alot but I'm guessing thats my voltage regulator clicking on and off?
Joined: Sat Dec 10 2005, 04:28PM
Location: United States
Posts: 4954
Very well could be. You can rig in a regulator form a C Bod with a couple of spade connectors and a small piece of wire. I forgot the part number, but they are readily available from Standard Ignition Parts. Try an independent parts store. Screw those no mind chains. Their criteria to work there is a pulse, and not necessarily breathing.
Joined: Sun Oct 16 2005, 01:22PM
Location: Nashville TN.
Posts: 10
Well I actually have already bought the chip and capasitor to replace the machanical regulator. I got the idea from this web site.( www.allpar.com/history/mopar/electrical2.html ) I don't know but it might be worth a shot if I can find the right wires to solder Heheh. Also I was wondering about the oil gauge, what does that meen when you ground the wire and the gauge goes full? Thanks for the help.
<span class='smallblacktext'>[ Edited Sat Jan 21 2006, 12:39PM ]</span>
Grounding the wire completes the circuit and allows maximum current flow through the gauge. Gauge should peg at high side. Doing this test rules out any problems in the gauge and it's related wiring. You say you have replaced the sending unit, but with the correct one? There are two types: gauge(like you have) and idiot light. If you can find a good auto parts store have them look up the sender. Tell them you have a gauge, not a light. The sender for the light is just an on/off switch triggered at around 10psi. Sender for gauge is a variable resistance unit that varies with oil pressure. The sender for the gauge has larger body than the one for the light. Size for gauge is about same as 35mm film canister. As for the needle moving back and forth; as long as distance traveled is less than the width of the pointer I wouldn't worry too much. I always enjoyed the waving temp and fuel needles in my old fury, let me know the 5 volt regulator was working and added character to the car.
Joined: Sat Dec 10 2005, 04:28PM
Location: United States
Posts: 4954
70 is right. The gauge unit will fit in the palm of your hand and the light unit will slip through your fingers.
One quick way of telling is to turn on the ignition, don't start the car, and see what the gauge does. If it swings to the top, you have the wrong sender unit. If it goes to zero when you start the car. . . . Bingo. Wrong unit.
The sending units for those had different values. Make sure you got the right one.
Joined: Sun Oct 16 2005, 01:22PM
Location: Nashville TN.
Posts: 10
I have the larger gauge type sending unit but when I ground it the gauge go's full but when I had it hooked up to the gauge it did nothing. so maybe I bought the wrong sending unit.
