# 1984 720 temp gauge, fuel gauge, and tach don't work



## montanahelp (Nov 13, 2008)

I know this truck is earlier than HB series, but I need some help. I have a 1984 720 pickup Z20 that I picked up after the engine was overheated. It was a project that the previous owner stopped midway through a head gasket project. I put a different engine in it and got it going ( running OK ). The temp gauge, fuel gauge, and tachometer all do not work. All the fuses look good in the fuse panel. The ignition key is pretty sloppy - don't know if that has anything to with the gauges. Any suggestions are greatly appreciated from a poor Montana mechanic on a low budget!


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## zanegrey (Dec 5, 2005)

check fusible links first..

also there is a 720 site.. for first hand info...


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## SPEEDO (Jun 9, 2003)

back in those days, the volt reg. was made into the fuel gauge... if the volt reg is bad, the fuel & temp gauge will not work. The tach... could be just a diode (inline) Like Zane said might try the 720 site


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## CMax03 (Jan 17, 2009)

pull the speedometer and stretch all spring loaded contacts especially if it contains a printed circuit beyond the instrument cluster!


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## Limptera13 (Jul 26, 2007)

what is the part number or how can i search for the part online or ebay or pep boys


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## SPEEDO (Jun 9, 2003)

The part number for????


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