Tach on '97 SN has a mind of its own..

[wtrskrs]

I've got a whacky tach (original Nautique gauge; had this same issue with my '96). The tach sometimes reads correctly, and sometimes it is much higher (and sometimes will bounce around). If I whack it with my knuckle, sometimes it starts reading correctly, sometimes not. I've ignored it because I have Stargazer, but along with some other covid-19 related maintenance, I'd like the tach to work correctly. I just bought one from Nautique Parts, and wasn't paying attention to the fact that it is Faria, the increments are 200rpm,(not 100rpm), and it doesn't say Nautique. Before I just slap the new one in, I was wondering if anyone else has seen this problem, whether it is tach failure and no choice but replace it, or if there is something else? I've tried wiggling the connectors a little, but not enough to do anything. I pulled the old one out, but if there is a chance that it is just connections rather than the unit being faulty, I'd rather put the original back in.

Any idea/suggestions?

Thanks,

Gordon

[gcam4]

Yep, I've seen this before. Our problem was a loose connection with some corrosion on the back of the tachometer. Pull the dash and check your connections.

Sent from my SM-N950U using Tapatalk

[SilentSeven]

That year / line of Nautique is infamous for being under-wired at the dash. When I had mine, I totally rebuilt and upgraded the power and ground wiring system to support an upgraded stereo headunit and Perfect Pass Stargazer.

If you're in there looking at loose wires per gcam4, also closely look at the harness connectors for corrosion or other problems. (Mine didn't show any visible problem btw) Consider running a dedicated ground from the tach to the battery as a test if you see nothing obvious with the wiring.