Temperature gauge not working...ideas?

[mlp40]

Hey guys!
Time to get a new idea on what to try to get my temp gauge to work on my 1971 Mach 1. I thought it might be the temp sender, put a new Scott Drake part in, no change. Also replaced the thermostat. Car warms up, I get good heat in the interior, but the gauge does not come off the C mark. I took the center trim out unplugged the leads to the temperature gauge and hooked it to a 1970 dash part that had a temp gauge, it did not work either. I have ruled out the actual gauge, thermostat, and sender. What electrical test could I perform? Any other ideas?
Thanks,
Mike

[Oztrailer]

Does the fuel gauge work? the temperature gauge needs the 5 volt supplied from the regulator on the back of the dash.

[mlp40]

Hi Steve,
Thanks for the question. Yes, the fuel gauge seems to work fine, as do all the other gauges, except the clock but thats a whole different issue. I was trying to think of a way to test something with my automotive meter but I'm not so good with that stuff.
Mike

[Oztrailer]

Is the sender you got for a gauge or a light? The sender for a light won't work for a gauge. It is basically an on/off switch.

[mlp40]

Hey Steve,
This is the reason these forums are so good. Thanks for the idea! I did not know there might be 2 different senders. I will call Dallas Mustang this morning and chase down the answer on that Scott Drake part they sold me.
I will let you know,
Thanks!

[Steven Harris]

Mike have you tried grounding out the gauge wire at the sender? If it is just the sending unit, with the help of a friend looking at the gauge, ground out the gauge wire at the sending unit on the block and the gauge should move. In basic theory gauges work on resistance therefore the greater the resistance the higher the reading. That should give you a quick answer and place to start.

[mlp40]

Many thanks to Steven and Steve O! Problem solved! Thanks for that simple question Steve O on whether I had the correct sender installed. I called Dallas Mustang and asked about the Scott Drake sender I bought. There was a pause and then they ask if they could call me back. When the call came in I was told they had received a large shipment of the wrong senders (the idiot light senders) and that was probably the cause. He gave me the Oreilly part number and it worked as advertised. Dallas Mustang said to bring it back and they would reimburse me. I thought wow what upstanding guys! But, who is going to pay me for all the hours spent tearing out the dash all the testing and scratching my head? I understand mistakes happen, but kinda weak for Dallas Mustang to make this mistake!
Again, Thanks so much!
Mike

[mymachone]

[quote='mlp40' pid='16257' dateline='1316835375']
Many thanks to Steven and Steve O! Problem solved! Thanks for that simple question Steve O on whether I had the correct sender installed. I called Dallas Mustang and asked about the Scott Drake sender I bought. There was a pause and then they ask if they could call me back. When the call came in I was told they had received a large shipment of the wrong senders (the idiot light senders) and that was probably the cause. He gave me the Oreilly part number and it worked as advertised. Dallas Mustang said to bring it back and they would reimburse me. I thought wow what upstanding guys! But, who is going to pay me for all the hours spent tearing out the dash all the testing and scratching my head? I understand mistakes happen, but kinda weak for Dallas Mustang to make this mistake!
Again, Thanks so much!








Nothing new there . I have a service business and many times we go to service heating equip and find it is so bad it needs replacement , it some times can take us a hr or more plus the special trip there.. We present a bill for service call and time on job and what we hear is , why do i have to pay , you didn't do anything ? WE then tell them how much it cost to just get there house and then they drop the bomb , well that not my fault , you didn't do anything I'm not paying.
GART JB ( my machone)

[Endroman]

Hey there mlp40, I actually have the same problem. Is there anyway u can tell me step by step how to change out this sender? I have never had this part of dash apart before. Also do u have the part # of this senser and what part store did u get from? Thanks for all your help!



uote='mlp40' pid='16156' dateline='1316648654']
Hey guys!
Time to get a new idea on what to try to get my temp gauge to work on my 1971 Mach 1. I thought it might be the temp sender, put a new Scott Drake part in, no change. Also replaced the thermostat. Car warms up, I get good heat in the interior, but the gauge does not come off the C mark. I took the center trim out unplugged the leads to the temperature gauge and hooked it to a 1970 dash part that had a temp gauge, it did not work either. I have ruled out the actual gauge, thermostat, and sender. What electrical test could I perform? Any other ideas?
Thanks,
Mike
[/quote]

[mlp40]

Absolutely glad too!
The sender is located just below the thermostat housing at the front of the engine on my 351 2v. It has a brown wire attched to it. You have to be sure to get a sender for a gauge and not for an idiot light. the O'Reilly part # SW2328. Its made by BWD and # on box is WT386. It cost about $8. I disconnected the brown wire, took a box end wrench and turned the old one out. I put a tray underneeth to catch the antifreeze that runs out, but if your fast its only about a qt or so. Tighten the new one and then reconnect the brown wire to it. Top off the radiator with the lost antifreeze and your ready to go. You dont have to tear out the center of the dash. I did because Dallas Mustang supplied me with the wrong sender so I did a bunch of other checks. Took me about 30 minutes.
Hope this helps!
Mike