I have worked on a number of Raydomes that had duckbills that had never been clipped yet did not seem to retain water. Certainly not the amount that was this one. The seal on the Navico is not near as robust as that of the Raymarine
If the plug has holes in they are microscopic and won't facilitate :
"If you mount the scanner on a pedestal or base, ensure that rain and sea spray can drain away rapidly, and the breather hole in the base can operate ."
I have had truly torrential rain blowing sideways the last couple of months. That hole would need to be wide open to hope to keep up.
I have never failed to clip the rubber tube drain, I feel I should have noted the blind plug. I also feel the directions are lacking.
I should point out that I enjoyed a long career of installation, repair and later design of equipment
. Had I installed this dome for a customer, any costs pertaining to the repair, beyond what the manufacturer is willing to do, I would have covered.
I will contact Navico, I am certain they have seen this before. It is entirely possible they will offer a replacement. I will post the results as well as their recommendations for the plug here.
I should point out that "legally" I voided the warranty by opening the dome. I also opened the base, removed, cleaned and have the printed circuit board under lamp. I am hoping that the rainwater did no permanent damage and will do some testing today.
I can hear the litigious screaming of my moronic actions and admissions.
Certainly I hope that Navico offers a complete replacement.
I have high hopes and low expectations. I don't plan to let it occupy my mind more than it has to.
Thanks for the words of support.
Looking for another pretty place to work on the boat.