How to replace portlight in head

[Moderator]

Has anyone removed/rebedded/replaced the portlight in either the forward or aft head? What is the portlight screwed into?

If we rebed the head portlights, do we need to cut away the fiberglass wall liner to get to some nuts, or is there a backing plate embedded in the fiberglass that the portlight fasteners are screwed into?

Just trying to understand how big of job it is before we start. We are rebedding all portlights as we found most of them leaked during our recent passage to Hawaii.

Marilyn, moderator

[Jeff]

Hi Marilyn,
I re-bedded my aft-head portlight a few years ago. I found that 2 of the aft screws immediately behind the bulkhead were almost in line with the bulkhead…but not quite, which enabled me to get a small open-ended spanner on to them. I’ve replaced the 12 internally accessed original Interscrews with 4mm st-steel bolts. The externally accessed screw-heads came out easily & were re-used. It turned out to be the easiest portlight to work on, out of the 4 that I re-bedded. I can’t remember exactly what the attachment of the forward screws was, & I didn’t take any photo’s, but I don’t remember having any particular difficulty with re-installing the window. If you treat the forward externally accessed screws with caution & they’re not too corroded you should be able to lift off the frame & then re-use them.
HTH, Jeff

[Moderator]

Thanks Jeff – I also answered my own question yesterday by removing one of the fasteners from the head window – it is a ss screw, not a bolt, so there is no internal fastener behind the head fiberglass walls. Once we rebed the head window, we’ll report what we find – hopefully it won’t be a soggy rotten piece of plywood.

On windows that require the exterior screw and interior threaded stud, we find the threaded stud has corroded to dust. In many cases, we can pull away the interior frame before the exterior fasteners are removed. Obviously a project long overdue – I will post more once we have finished this long job. We are replacing all fasteners as we go – they are readily available and affordable in the US from http://www.mcmaster.com. They call them “Low-Profile Binding Posts”. We bought the length for “3/4 to 1″ thick material”, but 7/8″ to 1 1/8″ might be better because some places, the plywood wall has swollen and the shorter studs are not quite long enough.

Marilyn

[Jeff]

….”We bought the length for “3/4 to 1″ thick material”, but 7/8″ to 1 1/8″ might be better because some places, the plywood wall has swollen and the shorter studs are not quite long enough.”

Yes, this was my problem too. The correct size just wouldn’t catch the opposing thread on swollen timber, even though I’d dried out the side panels ‘in-situ’ with my heat-gun. I eventually drilled out the holes & put in 1″ x 4mm bolts & just tightened up the whole lot until I was sure it was all waterproof. That resulted mostly in about 8mm of thread showing through the nuts so I cut each one down with a hacksaw so I could cover the nuts with a white plastic nut-cover. Looks a bit ‘industrial’ but I had difficulty sourcing the exact size of Interscrews here & IIRC they were over $1 each
Cheers,
Jeff

[Moderator]

I did rebed our head portlight and found everything in great condition. Only limited corrosion on the aluminum frame near the fasteners, and when replacing the screws, they gripped well into whatever is behind the nicely glassed porthole opening.

The portlight did need rebedding, as we are finding with all portlights on Rainshadow, because the original foam gasket between the cabin side and the outer frame is failing and allowing water in – especially around the fasteners.

Also, we have found some window glazing has failed, especially on the larger area portlights.

We’re in the process of figuring out what to do about improving ventilation (i.e. installing opening portlights?) and how to best fix leaks for portlights we just want to reuse. This has been a long project, but I think we might be getting to some good decisions, which I will report on later.

Marilyn, moderator

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