Gauges "bouncing" after repair

[jy2112]

Hi All, we recently had our '98 Maxum 2100SR serviced. New bellows, gasket kit, tilt sensor kit, water supply tube, and shift cable. Took her out and ran great for about 5 minutes before the all the gauges started jumping. This caused the alarms to go off. Oil level was fine, temp fine. The engine sounds and performs as it should but the random "jumping" and subsequent alarm would seem to indicate a short somewhere. Any thoughts on this? We are handy but not experts in the area of electrical. Could something be loose or disconnected as a result of the recent work?
Also, the gear case oil supply nipple had broken off during hose repair. The mechanic disconnected it completely and said the reservoir wasn't needed anyway as the newer models don't use this. Could this be part of the problem? Everything worked fine prior to this maintenance. Thanks for your input!

[mmwjr]

I disagree with the mechanic regarding that newer boat don’t use the gear lube reservoir. The older models didn’t have it but since some time in the 80’s it’s been standard. However that has nothing to do with the bouncing gauges which is either a loose postive or negative common wire. It could also be an issue with the voltage regulation by the alternator.

[jy2112]

Mike, thanks for your reply! We are thinking the same. I’m not comfortable with eliminating something that has been working just fine.
As for the gauges, I misspoke in my original post. The only gauges affected are the oil, temp and tach. All others are working fine. Not sure if that makes a difference, we still need to track it down but perhaps there may be an easier starting point knowing which specific gauges are impacted. Thanks again!
Jenny

[mmwjr]

Hi Jenny. The Speedometer doesn’t use electricity it functions on air pressure in a tube that connects to the outdrive. There is a small hole in the front of the drive that allows water in and compresses the air in the tube which intern moves the speedometer needle. The only other gauge that you didn’t mention that uses electricity is the voltmeter but that can get masked but a fluctuating ground of power wire. In short I still suspect what I posted before.

[jy2112]

Ok Mike, thank you so much, we’ll start digging! Jenny