Bolero does not have a bilge pump. There is little clearance, only about four inches or 10cm, between the cabin sole (the floor that you stand on) and the bilge (the inside face of the hull), so there is not much room to fit a bilge pump. In any case, I think it is better to keep the water out, than to attempt to remove it once it is in by an electrical contraption that is doomed to fail at some point. Also, if I can see how much water is coming in, I can determine whether there is a leak worthy of my attention.
Bolero's windows had been leaking, and various previous attempts had been made at repairs, which was evident from the uneven application of silicon goo and the odd-sizes of screw-heads used to fasten the window-frames to the cabin roof, including a couple of countersunk and oversized cross-head screws. The only way to find out how the things were constructed was to pull them apart, so I started by prising off the forward starboard window, which had been one of the leakiest.
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| Forward starboard window before repair |
I found that the windows were constructed in two parts; the outer frame with the glass, which was screwed onto the outer wall of the cabin, and a simpler, inner frame which was screwed onto the inside face of the outer frame, thus clamping the headliner or inner lining of the cabin roof into place. The strength of the fit therefore depended on the strength of the purchase between the screws in the inner frame and the screw holes in the outer frame. Over time, most of the screws had worn out their holes, Galvanic reactions had reduced the aluminium into a white powder and many screws had become loose. The previous repairs had attempted to deal with the enlargement of the screw-holes by using larger and larger screws, which was obviously unsustainable.
Having got one of the windows off, the first job was to clean off all the old goo. The best approach was a wire brush. This got down to the bare aluminium and revealed the extent of the pitting and loss of metal at the screw holes. I filled the screw holes with JB weld and re-drilled them before repainting the frames. For painting, I used Dulux metal etch primer and epoxy enamel. It took me several attempts to get a presentable finish. Next time, I would use a pot and brush, not a spray can.
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| Before and after cleaning the goo off the outer frame |
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| Close-up of pitting at screw-hole and attempted JB weld repair |
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| Making a gasket for the outer frame with 1.5mm thick rubber strip glued into place with black Fixtech 180 |
Re-fitting the windows took several attempts, too. I made gaskets for each window using 1.5mm x 16mm black rubber strip from the Big Green Hardware Store, fixed into place with black FixTech 180.
Initially, I tried to re-screw the two frames back into place, but the screws did not get enough purchase into the GRP hull and aluminium frames for a strong joint. The inner frames were a little smaller than the outer frames, but there was sufficient metal to drill through, at an angle, from the outer screw-holes to the inner frame for a through-bolt. The resulting protrusion of bolts on the inside face reminded me of the bolts in the neck of the cartoon character version of Frankenstein's monster, but it was a strong joint. I might even use some of the protruding bolts to fix brackets for curtains. Also, I found that my rubber gasket was too thin, leaving some big gaps between the outer frame an hull. I doubled the thickness of the gaskets by adding another strip, and then attempted a dry-joint, which leaked when subject to a garden hose test.
There were a couple of things that I tried that did not work. In an attempt to arrest the Galvanic reaction between the aluminium frames and stainless steel bolts, I coated the latter with Duralac. However, the end result was plenty of yellow cake that stood out proudly against the freshly painted black frames. Ultimately, I cleaned it off and used nylon washers instead; there would still be some aluminium to steel contact, but not as much as otherwise and in less visible places. Also, I initially tightened the bolts with my impact driver. Impact drivers are good for getting seized bolts out, but they over-stressed my bolts when I put them back in, bending several where the nut or head had not seated evenly on the frame. I finally tightened the bolts gently by hand, which left a little for further tightening if needed. Placing and tightening the bolts was a two person job, and my wife patiently helped by holding the spanner on the nuts inside the boat whilst I got to work on the dome-heads outside the boat with my screwdriver.
In an attempt to seal the gap between the gaskets and hull I initially thought of using silicon grease. However, the dolt at the shop sold me silicon bathroom sealant instead, and I only noticed when I had applied it and it had started to harden. I did what I could to get it off again.I hate silicon bathroom sealant on boats - it is not strong enough to hold anything, there is nothing you can do to it after it has set, it is too yielding to remove easily with a knife or scraper and is impervious to chemical attack. That's why I use proper alternatives such as Sikaflex and the FixTech Range. The latter has a purpose-built clear UV resistant sealant, which worked well to fill my gaps.
It took a surprising amount of time to get the windows back in, from February to April, including several trips to the bolt shop by my wife to replenish my stock of bolts, washers and nuts and several attempts to re-paint the frames. When the final hose-test revealed no leaks, my long-suffering wife and I gave a relieved cheer. Subject to the COVID-19 travel restrictions, we could finally take the boat out again for the first time since slipping it in January.
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| Windows after replacement, starboard side |
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| Windows after replacement, starboard side before placing dome-head nuts on the protruding bolt-ends |
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