Leaking Lewmar Opening Portlights

jac

jac

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One of my opening portlights seems to have developed a slight leak. The lewmar site says this..
Possible leak paths are:
Under the lower frame. This is caused by insufficient bedding compound between the low frame and the deck, or the compound breaking down over time. It may also occur if the cut out in the deck is too big or the hatch/portlight is not mounted on a flat surface. This is a build or installation problem.
Between the lower frame and the rubber seal (gasket). This may be caused by the upper frame being distorted or a loss of seal pressure. Lay a straight edge along the sides of the hatch and also diagonally across the lid to check for twist. Also check the seal for dirt or damage. Try closing the lid down on a sheet of paper. If the paper can be slid out when the hatch is closed the seal is not compressing.
Through the holes in the acrylic used on some products to fasten the handles, hinges or friction levers. The handles have a standard O-ring under the plastic moulding on the outside of the acrylic. This should be cleaned and lightly lubricated with silicone grease.
Between the acrylic and the upper frame. (Not Standard portlights and Concept hatches.) This is caused by a breakdown in the adhesion between the sealant and the upper frame or acrylic. Try gently pushing the acrylic up out of the frame and look for movement. This type of leak is the least common.


Has anyone successfully tracked a leak in a lewmar opening portlight and got any tips. (It's not dirt on the seal as were cleaned (gently) in the summer and again before the winter and no sign when I checked yesterday and suspect not a build problem!)
 
I have had this problem and been through all the steps on your post. My port lights were the older type with the join in the frame halfway up. Water was getting into the frame and coming out at the bottom where the catches locate. This is a common failure with this design of port light. Lewmar tell you to put some sealant in the join but I found that didn't work. The answer for me to inject silicon sealant into the hollow frame through the holes on the inside. If you squirt it in below the horizontal join (left and right) until it comes out of the holes where the catches fit, you would have filled the frame with sealant. Mine haven't leaked since. Hope this works for you.
 
jac said:
Has anyone successfully tracked a leak in a lewmar opening portlight and got any tips. (It's not dirt on the seal as were cleaned (gently) in the summer and again before the winter and no sign when I checked yesterday and suspect not a build problem!)
Click to expand...

Have changed a seal - bit fiddly so give yourself plenty of time. Seals should last for years if kept reasonably clean, so unless there is a nick in it this may not be your issue.

The O rings are easy to do.

Also re-bedded a couple, which seems, at least on my boat, a much more likely area for problems.

It is probably best to get the hose on it from the outide, and then go inside and take the trim off until you are certain where it is coming from. It is annoying to 'solve' one problem only to find you have solved the wrong one!
 
Yes.

I've had 2 problems.

1 turned out to be the foam gasket going hard and breaking-up. This involved removing the frame, cleaning off the old foam gasket, and re-betting using Abromast Butyl sealant.

The other was the perspex not sealing. This was due to it being opened and closed a lot of times which had bent the tangs on the catches out a bit. I just tapped the tangs back gently with a drift and a hammer.

First job is to get someone to put a hosepipe on the window and watch where the water comes in from. This will tell you what the problem is likely to be.

Hope that helps.
 
I have seven Lewmar Old Standard Size 1s on my boat, and they were all leaking or dribbling to some extent. I went for the most likely option and changed the seals. Originals are horribly expensive, at £30+ each, but the nice man at Seals Direct suggested that I use 8mm expanded neoprene cord, butt-joined with superglue and held in place with silicone sealant.

Which I did, and there hasn't been so much as a drop out of any of them since. By the end I could do a seal in about half an hour, and the total cost was around £14.
 
Thanks all, they are the older type with the join 1/2 way up. I was thinking o rings so pleased to hear it's not a big job to do that but will definitely use the hose to do so. Just need to wait for Deacons to finish installing the infrastructure on the pontoons so that a hose will reach!
 
Hi,
I had exactly same problem on same model of boat. Solution was to apply several doses of Capt. Tolley along the top edge of the frames, with all the recent rain we have had no leaks.
 
Tex said:
Hi,
I had exactly same problem on same model of boat. Solution was to apply several doses of Capt. Tolley along the top edge of the frames, with all the recent rain we have had no leaks.
Click to expand...

That'll be the foam gaskets shot then.
 
Tex said:
Hi,
I had exactly same problem on same model of boat. Solution was to apply several doses of Capt. Tolley along the top edge of the frames, with all the recent rain we have had no leaks.
Click to expand...

Capt Tolleys is a hell of a lot quicker than anything else and given the length of the list (which is now longer than when I started) it may the way that I go.
 
jac said:
Capt Tolleys is a hell of a lot quicker than anything else and given the length of the list (which is now longer than when I started) it may the way that I go.
Click to expand...

It may be OK for a very short term fix, but unless you are absolutely certain of where the problem lies, I wouldn't rely on it for a long term solution. The trouble is that it seals at the narrowest point, which may not be where the water is getting in so you could still have hidden problems of water penetration, frost damage and so on. The only good cure for a leak is to dismantle, clean and rebuild.
 
I began to see leaks with 2 of my lewmar windows after the boat reached 15 years old, decided to make a winter project to refurbish the lot, including replacing the crazed Perspex. What was interesting was that I had assumed the leaks were the Perspex to frame rubber seals, but on removal it was obvious that the problem was the perished sealant between the frame and the GRP.

Rebedding with the butyl compound, and no leaks since........
 
JumbleDuck said:
It may be OK for a very short term fix, but unless you are absolutely certain of where the problem lies, I wouldn't rely on it for a long term solution. The trouble is that it seals at the narrowest point, which may not be where the water is getting in so you could still have hidden problems of water penetration, frost damage and so on. The only good cure for a leak is to dismantle, clean and rebuild.
Click to expand...

I would agree with this process. On my windows previous owners had blasted the windows with everything to prevent leaks. In the meantime the actual source of the leaks had never been cured and water proceeded to fill the frames, rot the aluminium, pool in the gaps between the frames and lining that were isolated with copious volumes of sealant. The mess was incredible and I ended up having to remove rotten wood, aluminium frames, head linings and a damaged bulkhead. Leaking windows will wreck your boat much faster than you think and cost significantly more in pounds and time than if you now prioritise your repairs and fix the window correctly. In the end I removed all my windows and had them professionally refurbished and the boat is now very dry. I am still dealing with the effects of the accumulated water damage 2 years later - this winter the fore cabin refurbishment. If ever the adage a stitch in time was relevant to a situation it is the prompt repair of leaks in yacht windows and fittings.
 
Thanks. Obviously first need to trace exactly where the leak is. For a while I also thought we had a second one by the chain plates but I think it's coming down from the portlight than going inside the moulding and spreading out! Can see tracing being a fun job.

From what I understand, the inner trim on Lewmar old standards is basically only Velcro'd on. How is the outer one attached?
 
Presume you mean the main window frame? My lewmar windows are secured by machine screws which are accessed once the inside trim is removed, and go into tapped holes in the frame
 
West Coast said:
Presume you mean the main window frame? My lewmar windows are secured by machine screws which are accessed once the inside trim is removed, and go into tapped holes in the frame
Click to expand...

Perfect - yes I did, sorry , shouldn't post in a hurry!!! Couldn't see any external fixing and internal ones were tough so stopped trying to remove until I could get better internet service and confirm that they were Velcro'd on and therefore not break it and make the to do list even longer!!

cobolt said:
Hello all,

For those with old standard portlights, as it seems the OP does, this document may be of help in identifying / fixing a common leak path.

https://dl.dropboxusercontent.com/u... - Portlight - Old Standard - Frame Leaks.pdf
Click to expand...

That is just the sort of doc I wanted. We see the water by the latch hence my original thought of the o ring. It looks like an official lewmar doc - is it?? Interesting that it says not to remove the portlights but fix in situ.
 
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Some of the machine screws on mine were hard to remove (bottom, middle, late 80's boat). Used combination of light taps on an impact driver and a brace with the bit from the impact driver to get them out in the end. Worth greasing them up when you put them back in.

Water seems to accumulate in that latch tray with leaks from several places. Probably worth looking at the o-rings first as they take seconds to take out and change, but really you need to try and flood it all from the outside so you can get enough inside to be easily traced.
 
cobolt said:
Hello all,

For those with old standard portlights, as it seems the OP does, this document may be of help in identifying / fixing a common leak path.

https://dl.dropboxusercontent.com/u... - Portlight - Old Standard - Frame Leaks.pdf
Click to expand...

Many thanks for posting that link, Ours leaked and new seals and a few new latches have apparently solved it, but we paid somebody multiple dollars to do it and it was a long learning curve, I have printed off that document for future reference, Initially I could not even see how the latches were assembled.

Somebody here suggested greasing the seals with Vaseline, all that did was to create a greasy mess making fitting new seals harder. With our latches the socket bits were tightened down way too much by the previous owner, no doubt hoping to cure the leaks bu tin vain, it just made it almost impossible to close the open acrylic and stupidly I used molegrips with the inevitable result of broke latches, our latches were also too tight in the acrylic making them very stiff to turn even with the pane open and under no load.
 
cobolt said:
Yes it's an official document, I'm the marketing manager at Lewmar. I'm glad it's of use, see Pye-End's post as to why it's better to fix in-situ :)
Click to expand...

Blimey cobalt, you being the Marketing Manager is a bit of a result. Mine are old Standard portlights so this level of service is great. Have you considered putting this doc (and others like it) on your website so your customers can self serve?

One question - in the document it refers to leaving the portlights in place but removing any sealant and replacing with silicon. I assume this relates to sealant in the join between the top and bottom halves? Secondly any specific silicon sealant recommended or is it a case of whatever the swindlery has on offer that week is fine?
 
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