A number of years ago I purchased a
Raymarine ST40 Bi-Date Speed/depth/log instrument that comes with two thru-hull transducers.
Due to the layout of the inside with a shallow bilge and the intake and outflow thru hulls for the head that had been installed forward I installed these thru hulls port and stb beneath port & stbd settees as close to centerline as possible beneath these settees. The problem is that when the boat heels more than say 15 degrees either the speed or depth transducer stops working.
The diagram below illustrates the bottom of my hull and shows approximately where the existing thruhulls for the marine head and the transducers are located and where I can move them. The locations available are limited by a depth beneath the floorboard of less than three inches between settes and in head area. Where I have indicated is under the vee berth behind the water tank whereas the head thru hulls are fwd of the water tank.
diagram at
http://fulltilt2pics.angelfire.com/thruhulls.GIF
The transducers are sealed with 3M 4200 I believe.
My plan is to remove them and then fill the holes using West or East system
epoxy grinding a tab angle both inside and outside the hull.
I would start by placing plastic wraop on the outside of hull held in place with tape. Then I woudl move inside and put a layer of cloth just larger than the hole in place, followed by glass matt the sise of the hole followed by glass cloth increasing in diameter (2 layers) over the matt. I would then saturate with resin (I would use fast hardener) and then move to the hole on the other side and repeat.
After a suitable time period (maybe an hour?) I would go outside, remove the plastic wrap and apply two - three layers of cloth and resin on each hole. Not sure how to stop it from dripping but suspect plastic wrap and tape could be used to hold in place.
Repeating this process of alternating between inside and outside I would build up the patch to the thickness of surrounding hull. Then wait 24 hours to cure and apply thickened
epoxy witha sandable filler (probably west 407) to build up to a smooth surface - sanding with 80 grit and Random orbital sander. Also inside.
Any comments on transducer locations? Will the flow over fwd head thru hulls affect in any meaningful way?
Any comments faults with patch plan?
What does
epoxy need to be overcoated with before applying bottom coat (Micron CSC)? Inside I would use a primer and then a bilge
paint.
Thanks
Mike
Full Tilt 2