Heat gauge question

[bigdon-70blazer]

My heat gauge on the instrument cluster does not seem to work now, did before the rebuild. The needle is pegged over past the hot area when I turn the key on but stays over there all the time unless I unhook it under the hood. Any simple fixes here? I did try to take some wire and ground it separately but no help. Any gurus know about this? I changed the original cluster lens and bezel and cleaned the rest very carefully. Help ! but almost done!

[John H.]

It is grounding out somewhere. Did you change your sending unit? Might have the wrong one or the wire is grounding itself out.

[THENEWMEXICAN]

i have the same problem with my Blazer BUT i think mine is wiring issue for sure. when the original owner swapped the block and tranny they made all kinds of messes with the wiring. hell, i have two sending units! and i don't know how many amps they should be pushing nor if i even need two... but yeah, i run at hot and after i replaced the thermostat and did a flush i'm pegging past hot. whatever you figure out let me know cause i'm about to wire up a temp/oil/volts gauge cluster somewhere. attached are a few pics of my sending points:
when i unplug this one the gauge goes cold...

when i unplug this one nothing happens but when i plug it back in the guage will run to hot...

[THENEWMEXICAN]

check out http://67-72chevytrucks.com/vboard/s...d.php?t=333575

[bigdon-70blazer]

I bought a new heat sensor and will try that one. The old one was original. Maybe that is the problem. But will have to wait until next week as I am serving the US Air Force this weekend!

[72Levi]

You have a bad temp gauge, mine did the same thing, replaced the gauge and all ok.

[bigdon-70blazer]

Originally Posted by 72Levi

You have a bad temp gauge, mine did the same thing, replaced the gauge and all ok.

Does the gauge and the light in yours work? I don't know if I have seen that the light works, it doesn't come on when started.

[bigdon-70blazer]

Looks like I am getting ready to change the gauge out in the cluster, is this hard to do? I have had the cluster out and changed the lens and bezel before.

[addicted2dunes]

Originally Posted by bigdon-70blazer

Looks like I am getting ready to change the gauge out in the cluster, is this hard to do? I have had the cluster out and changed the lens and bezel before.

Nah, just take the cluster out like you did to do the lens, just a couple more nuts to take off to release the gauge from the back plate.

[old man jimmy]

Originally Posted by bigdon-70blazer

Does the gauge and the light in yours work? I don't know if I have seen that the light works, it doesn't come on when started.

if you're running both the gauge and idiot light. The light should come on when you turn your key real slow towards start. Just before the starter kicks in the light should come on. It's just a bulb check feature.

[72Levi]

Light worked but did not come on, just gauge would peg to 'Hot' and wiring was good. The gauge was bad, it was easy to replace I even did it with the cluster installed. I just reached behind and got under to remove screws.