Venturi hole size/shape on Swordfish S

Seeking advice and experience please.

Had a hull leak in my Swordfish S at the Venturi holes.

A friend helped me epoxy the leak but it reduced the diameter of the holes and of course it no longer drained very well.

Grinded the holes so they’d be closer to the original size and some drainage improvement but still had an inch or more water constantly in the footwell.

Grinded the holes a touch further and I’ve brought the leak back.

Took it for a professional repairer and the guy heard me saying I want to expand the holes. I meant the narrower epoxy filled holes and get it back to the original size/shape whilst stopping the hull leak.

Well he has enlarged the holes more then the Fenn design and made them funnel shape. It doesn’t drain properly leaving an inch or more water in the footwell. It also feels like it’s added drag and I’m slower for more effort.

Solutions?

Put a bullet behind the Venturi drain? Cheaper and easier.

Get the holes remoulded to the original size?

Thanks

Scott S

I had a SFS that leaked from the venturi holes. I also added some material around the holes and they got smaller but the boat still leaked.

I ended up sanding them with a Dremel tool sanding bit, larger than the original holes. I saw the putty compound that spans between the bucket and lower hull was cracked all over, allowing significant water to leak in the hull through the venturi chute.

To fix this I removed the venturi cones, taped flush across the bottom hull covering the venturi ports, built cones on the top of the venturi ports out of tape , then filled the venturi holes with quick set epoxy and sucked into the drain hole for 10 seconds until I saw the epoxy suck into the cracks. Then I released the vacuum and refilled the venturi with epoxy.

After it cured I drilled out pilot holes then sanded them with a Dremel tool back to size leaving 1mm epoxy as a buffer, but the holes were still larger than from the factory.

Then I installed new venturi cones AND bullets. Bullets are key! They reduce draining speed from around 6mph to 4mph. This means your boat drains earlier and faster, as most people can maintain 4mph but not 6mph as much.

I love bullets and always install them on my boats. I recommend them for the SFS based on my experience. Fix the leak if yoy have a similar problem with cracked filler in the venturi tube

Thanks MCImes. Very helpful. The repairer did a similar, vacuum infusing the leaks with epoxy.

I’ve ordered some Orka bullets.

Do you think the venturi hole size has much effect on the drainage/water in the footwell?

I think the original Swordy holes were around 14 mm diameter but on a Stellar ski the Venturi holes are 22 mm. I’ve got the option now to fix it and choose the hole size.

Easiest way is to install tubes. I have been doing it for years. I drill out to 16mm and insert SS tube as that's what I had but have now got some carbon tube that is on its way, 16mmOD X 13mm ID

Years ago we got hold of a scupper kit and installed bullet scuppers on our Fenn skis (Mako6 and Double) and I think the same procedure would hold true today.

www.surfski.info/tips/story/1055/bullet-scuppers.html

The bullet kits come from Republic Sports:

republicsportadventure.com/

The procedure might be the same but the republic adventure website apparently isn’t. Don’t open at work!

zachhandler wrote:

The procedure might be the same but the republic adventure website apparently isn’t. Don’t open at work!

Ouch!

Yeah - their old domain was stolen and linked to a porn site.

I've edited the post with the new URL!