Temp gauge issues

[emac]

got the V8-380-c-d. having issue with i think the temp guage. It keeps dropping to zero, makes me think its a loose wire. I did change the impellar last night, ran it, temp climbed to 180 before dropping to 160 so seems like the t-stat is ok. shut down, restarted after letting engine cool, and it read zero again. Used a laser thermomoter to check engine temp and hottest spot was 157 at the riser. So i'm wondering if theres a temperature sending unit or someithing, or where would the wire for the temp attach at the engine. I'm kind of assuming is part of one of the clusters at the back of the engine. Thanks, any advise appreciated.

 

[sandkicker]

I'd start by checking the quality of the +12V connection to the gauge at the dash.

 

[emac]

I'd start by checking the quality of the +12V connection to the gauge at the dash.

Will do. I've had to redo the ends of a few wires under there already, so that makes sense.