Gemlux Thruhull Duckbill Scupper

[Surfnski]

Anybody use these to plumb the scuppers out the back through the transom?

Thinking about trying this to eliminate the through the deck scuppers. Anybody try this with success? Looks like I could gain an inch if I fill in the pocket even with the gutters. Pics to follow.

[Basketcase]

Originally Posted by Surfnski

Anybody use these to plump the scuppers out the back through the transom?

Thinking about trying this to eliminate the through the deck scuppers. Anybody try this with success? Looks like I could gain an inch if I fill in the pocket even with the gutters. Pics to follow.

I dont understand the hate for the thru deck scuppers. I like them on my Sceptre. They work great. Much better than the through the transom ones on my aquasport. I see a lot of people looking to change them, so there must be a reason.

[Jasnyder1]

Yea I’ve used them through the transom on my last boat with the duckbills and they worked great. I never had water come back in those scuppers at all, drained very well.

[nate22]

Originally Posted by Basketcase

I dont understand the hate for the thru deck scuppers. I like them on my Sceptre. They work great. Much better than the through the transom ones on my aquasport. I see a lot of people looking to change them, so there must be a reason.

I agree. I think draining water out thru the deck might be the best option for a stock floor height. No fittings or hose to fail, simple design. The only draw back to this is you cannot add a check valve to stop water flow back inside of the boat. Most likely why people try to re-rout them out the back of the boat.

[Old Goat]

Could you provide a source for the "duckbills"?

[nate22]

Originally Posted by Old Goat

Could you provide a source for the "duckbills"?

http://www.gemlux.com/catalog/Forged-Thru-Hulls

external mounted https://thmarinesupplies.com/products/duck-bill-scupper

[Old Goat]

Originally Posted by nate22

http://www.gemlux.com/catalog/Forged-Thru-Hulls

external mounted https://thmarinesupplies.com/products/duck-bill-scupper

Thank you for that.

That's very similar to the one's on my 78 Seafari originally. They always worked fine for me.

[nate22]

Originally Posted by Surfnski

Anybody use these to plump the scuppers out the back through the transom?

Thinking about trying this to eliminate the through the deck scuppers. Anybody try this with success? Looks like I could gain an inch if I fill in the pocket even with the gutters. Pics to follow.

I am debating the exact same thing now for my 23 rebuild. I purchased a set of the Gemlux thruhulls with the duckbill inserts for my boat. I was going to install them but noticed that I would have to mount them almost below the water line, in-order to get them to work at my stock floor height. The problem is the 14 degree transom angle, You have to mount the thruhull lower in order to insure the barbed tail is level with the floor height. I was not sure how effective they were going to be with keeping water out and started looking at other options. Also make sure to check for trim tab clearance.

I attached a picture of a diagram someone else draw to help explain. I purchased the longer 4.5in model. Looking back the shorter 2.5in model would have been better to help keep the fitting higher above the water. The barbed tail end has to be floor level for it to drain properly.

[Surfnski]

Originally Posted by nate22

I am debating the exact same thing now for my 23 rebuild. I purchased a set of the Gemlux thruhulls with the duckbill inserts for my boat. I was going to install them but noticed that I would have to mount them almost below the water line, in-order to get them to work at my stock floor height. The problem is the 14 degree transom angle, You have to mount the thruhull lower in order to insure the barbed tail is level with the floor height. I was not sure how effective they were going to be with keeping water out and started looking at other options. Also make sure to check for trim tab clearance.

I attached a picture of a diagram someone else draw to help explain. I purchased the longer 4.5in model. Looking back the shorter 2.5in model would have been better to help keep the fitting higher above the water. The barbed tail end has to be floor level for it to drain properly.

What if you did it this way?

[Surfnski]

Here are a couple pictures that may help show how I plan to do this. I'm going to glass a piece of 1-1/2" fiberglass tube to the rear pocket and connect that to the thruhull with a short piece of hose.

I thought about using the shorter 2-1/2 thruhull but I didn't think it would be long enough by the time you put the nut and pipe connector on it.

My center console has twin I/O's so it's a bit stern heavy. I dont hate the thru deck scuppers but it sure would be nice to be able to use the boat without the plugs in and not have water coming in the boat.