Question on the Hull Leak Test - Pylon vents

I have an 81' Hobie 16 and do find that there is water in the hulls after sailing. In light conditions I have come back essentially dry. In heavy conditions I tend to come back with quite a bit of water in the hulls with the Port hull having the most by far. When I say a lot I mean I pull the plug and water streams out like a hose for a bit.

In heavy conditions and when flying a hull the leeward hull definitely takes some water over the top and lots of spray. Add some poor crew balance and you can get a lot of water rolling over this vents in a day of sailing. Ocean sailing

I did the leak test by blowing into the hulls:

On the Starboard hull I would get some blowback meaning that I could essentially pressurize the hull by blowing into it rather quickly. The only place we found air escaping was at the rear of the Pylons going into the hull and that appears to be where air should escape.

On the Port hull I could not pressurize this hull and the only place we were able to find air escaping was via the rear of the Pylon but in this case a lot of air was able to pass to the point you could easily hear it blowing out.

Placement of these vents appears to be a curious design decision. After reading a lot of posts and seeing that Hobie hulls tend to come back with water inside, it sort of left me scratching my head as to why a tube was not installed and run up to release by the tramp and possibly curved like an upside down J to keep water from entering but allowing pressurization to occur.

Not sure which condition is normal, being able to pressurize the hull by blowing or not. My guess is that I should be able to pressurize the hull.

Given where I found air escaping, matching this to the amount of water found in the hull and then looking at the conditions it seems to make some sense.

If anyone could shed some light on this I would be most appreciative, it has to have come up.

If both hulls are getting that much water in them and one of them has only a small amount of air coming out of the vent, I would venture to day there is another path the water is entering from.

Here are a few simple things to look for when you go out:

I know it's obvious, but check to see if your drain plugs are in tight. Also check to see if they have O-rings. These do come off from time to time.

Verify that air is only coming out of the vents in the pylons and not anywhere else in or around the pylon.

Recheck the hull to deck joint all the way around each hull.

Check the seal around the ports if you have any. The flexing of the deck can open this joint while under sail.

This is all I can think of for now.

_________________
Nick

Current Boat
In the market
Previous boats owned
'74 Pearson 30
'84 H16
'82 H18 Magnum
St. Louis, MO

The vents are located inside the front pylon only. It's a small plastic tube that runs through the foam insert in the pylon.

What you have found are leaks around the pylon where it enters the hull - especially in the "track" section (since the pylons on older boats are the same extrusion as a sidebar - new boats have a purpose made extrusion without a track for this very reason).

A liberal application of silicone sealant will take care of your leaks.

What I did to my seal the tracks of my pylons to deck was I picked all the old silicone with bent screw drivers pics and wires from the track, lots of work to get all that crap out looking with flashlights into the track etc.

Then poured a small amount of resin into the cavity saturating the foam and filling until it over flowed a bit, cleaning the excess from the deck with thinner.....then I painted the entire hulls with gelcoat...thats another lonnnng story.....I finished spraying the hulls yesterday (Sunday).

I bought a digital cam at Costo last friday so Ill be posting pics soon....+ all the ones I have on disposable cams from the entire proyect.