Have a customer with an 04 353,says his gauges (Livorsi branded as Gaffrig I believe)sometimes fog up after a long day on the lake,but not all the time.Stored on a lift in a boathouse. We have looked at them but they aren't fogged unless it is run a lot. Haven't run in to this. Any ideas? What about drilling a vent hole in the back of the gauges?

I've seen it happen to mine a few times overnight. A good day in the sun seems to take care of it. Don't know about venting - I'd check with Mike Livorsi on that one.

Gauges are a lot like car headlamps etc... the glass should be sealed to keep out moisture. Example, wash your car or truck, park out in the sun, if the ureathane or silicon seal is broken, your headlamp will fog up. Similiar case here, if the gauge wasn't sealed properly from the factory or the seal was broken moisture will find it's way in. The fog is the moisture being evaporated then condensing on the glass because it's got no where to go. The solution would be to either 1. Buy new gauges 2. Try to re-seal them 3. Buy newer boat!

I would pull them and try to find where and what their sealed by. You might be able to run a small bead of silicon or urethane around where the glass meet the gauge to re-seal. Or simply take a heat gun and heat up the seal a let cool. A little heat might be enough to heat up whatevers there and re-seal it. I've done that to car headlamps, to stop the headlamp from fogging with great success.

Just talked to a nice guy from Livorsi,said that almost never happens,gauges are sealed,suggested I send them back and let them evaluate and repair.I will wait tillthis fall to do it,customer is using boat a lot now,doesn't want any downtime. Couldn't ask for better service than that.

I agree. I sent a pair of 5-year-old tachs back to them because they didn't seem right. They checked them out, recalibrated them and sent them back at no charge. Turns out the real problem was a blown diode in one of my alternators. (Whoops.....)