Rainwater ingress in quarter tonner. Opinions

[fishermantwo]

The photo is of the toe rail on my Ben Lexcen quarter tonner. The deck is fibreglass with end grain balsa in the cabin top and cockpit floor, the rest solid glass. The hull is half inch plywood with a Dynal coating from new. The hull sides on the inside above where the quarter berths would be if I had them has several rotten patches. Fixing the soft patches is no problem, solving where the water comes in is what's driving me crazy.

The water is obviously coming in when we have heavy rain periods and especially with driving winds. Light drizzle does not get in. I have raked out the filler between the deck and the toerail and resealed with Sikaflex.

Under the toe rail against the hull is a strip of bare timber, looks like teak but is probably beech. This is often damp and some mildew after a few days of rain.

I'm starting to think that when its raining heavy, the water runs down the deck spilling though the holes in the toe rail and is going up hill a bit into the bare timber. The window frames is another likely source but they look fine . If water came from the windows I would expect some water to show directly under them where the roof lining is loose.

Any words of wisdom appreciated

 

[Grajan]

Water can certainly travel uphill or could this have been a impact point on some occasion and there has been some delamination of the ply or even a piece of ply that didnt come up to spec ? We had limited success repairing this type of problem by drying out and applying thin Epoxy resin using a thin drill and syringe but the ply must be bone dry.

 

[Eygthene]

My quarter tonner is all GRP (Eygthene 24) but it too has an alloy toerail, through bolted at 4" intervals, with 1/4 " stainless steel bolts that pass right through the deck and a rubber gasket and the lip of the hull to fasten with nuts and big washers under the lip of the hull.

I imagine yours must be the same, but with the beechwood timber, glued to the hull to form a similar lip. Since you didn't mention bolts, perhaps your toe rail is screwed down into the timber.

I think your leak may be where the bolts/screws pass through. I cured several leaks where through-fasteners on the coach-roof and deck were causing a problem, by removing each fastener in turn and putting a squirt of sikaflex down the hole before retightening it.

 

[fishermantwo]

[ QUOTE ]
Water can certainly travel uphill or could this have been a impact point on some occasion and there has been some delamination of the ply or even a piece of ply that didnt come up to spec ? We had limited success repairing this type of problem by drying out and applying thin Epoxy resin using a thin drill and syringe but the ply must be bone dry.

[/ QUOTE ]

There has been no impact. The damaged area is further aft, I just used this area to show the cabin window etc. The yacht was built in 1970 and the ply looks like about 7 layers of cedar. I'm sure its top quality ply.

I considered the through bolts and will try the sealant trick as well.

Thanks for the help.