Predrill a hole through the plate and transom. Then take some marine sealant /adhesive 4200 and put a ring around the screw holes on the transom. Place the plate on the transom and start both screws down. When they are almost seated put some more sealant on the screw heads and tighten them down and your done. The sealant under the plate will seal around the holes and no water will get in. From what I was told from the dealer there is only a small amount of wood in the fishmaster transom near the motor mounting holes. The rest is aluminum, there is no wood down low.

Regular marine silicone does not stick very well to the starboard type material the plate is made out of. I also ran a bead of silicone around the edge of the whole plate on mine and it did not stick and I ended up peeling it off because it was not needed.

 

I tried all of that on my FG Thompson and still had it seeping for a season. Solved it by mounting the transducer with ss screws to a block of composite decking about 3" square, and then just using GE silicon sealant as an adhesive to fasten the block to the hull over the original screw holes in transom. Problem solved

Mounting a transducer mounting plate on a 2018 Statcraft Fishmaster and looking for some guidance. Should I predrill a hole and drive in a self tapping screw with marine silicone? Not sure what is behind the aluminum? Wood? Appreciate any help you guys have to offer. Thanks!

 

I'll use a piece of 1" x 4" x 8" piece in case of maybe down the road adding another transducer then I have room for another. I don't pre-drill any holes just use self tapping stainless screws just long enough to get a few threads thru the transom to help hold the composite while the GE Silicone Adhesive sets. I pre-drill the Composit for the self tappers, countersink both sides, then put your Silicone Adhesive inside the perimeter of the board but outside the screw holes. This does 2 things, provides a gasket for seal and adheres the board to your hull. You can also add a few lines inside the circle for added grip. Fill the countersunk areas facing the hull so when you run the self tappers they are also sealed. After the screws are homed seal over the top of the heads. Give it a few days to set for best results. I like to silicone around the 4 sides when it's all done as well. Here's a pick to help.

 

Pops, did you copy & paste that drawing ? I'd like to learn how to draw basic things like that on the computer. If you used computer program please state which one. I'd like to become proficient with AutoCad eventually but have never had any formal computer training. Sorry for the thread hijack....Mike

 

firemanmike.. I used paint and drew it..

 

Pretty much Orthographic projection on the diagram.

I don't mean to split hairs on the topic, but the pictorial shows countersink's on one side and counterbore's on the opposite side of the through holes.
The countersink on one side is good enough. You don't need them on both sides. A good sealant on the screws will be good enough for no water leaching. Sealing around the pre-drilled holes and the perimeter of the plate is good too.

Just my 2 cents worth.

 

Thanks. I never realized that was an available tool through Paint. Guess I need to invest a little time & work with it some. My 'free' computer time is generally spent reading or working with software upgrades on Fire Dept.programs. Mike

 

While were hijacking threads..... I have heard marine sealant doesn't last forever. Should you ever consider pulling those screws out and resealing?

 

Not marine.. GE Silicone adhesive.. You won't pull it off without a pry..

 

Thanks guys!

 

Glad you saw that Hook.. the reason for the one that faces the hull is so it keeps sealant there while pushed to the hull and seals the screw as it enters. The outside is done so you can seal the hole with the head in it. Thats why.. you do it your way.