Temperature Guage on 2005 Stingray 185ls (Volvo Penta 3.0L) not working

[bfield75]

New to boating. Just bought the boat recently and on my first trip out noticed that temperature gauge never moved off lowest reading. What should I check first?

 

[Bondo]

Ayuh,.... Welcome Aboard,.... The sender is in the t-stat housin',.....

Pull the wire off it, 'n ground it out,...

With the key "On", 'n the wire grounded, the gauge should peg to Hot,....