Hello, I have a 90' wellcraft nova with oem gauges and had my temp gauge rose above its normal operating temp( 150 gauge reading,140f stat) towards 180-190 so I shut it down, so I assumed ok new stat . So I pulled stat tested it on the stove and felt it opened a little hot (150-160f) . Before I put a new stat in I went ahead and put back in and fired It up again and this time the gauge only read approx. 120-130f. So as a precaution I put a new mercruiser sender along with the new 140f stat. After all of this the gauge now still reads low. When the gauge went high I figured it was a legitimate reading as the secondary sender showed a hot engine. The engine water temp leaving is every bit of 140f-150f when I touch the sender wire to the block it pegs the temp needle and disconnected it falls to 0. Does anyone have any input as to what would cause my symptoms and how to test gauge or does it sound like I need a new gauge? Thanks.
