Lewmar Opening Port Gasket

[John Langford]

I was getting leaking from one of my Lewmar #1 opening ports (1998 vintage). I read all the posts on the topic, replaced the two o-rings on the locking handles, and checked the frame bolts for tightness (they were tight) but the leak persisted. The frame sealant looked good and the water seemed to be coming from around the base of the black rubber gasket. So I removed the gasket, cleaned it and tried to refit it. And here is where I ran into a problem. It didn't seem to want to stay in place so I ran a bead of sealant around  the narrow crevice in the frame that was designed to retain the thin edge of the gasket and pressed the gasket into place. This seemed to work. A day later I sprayed the port with the hose and it seemed to be dry. But I haven't had a solid two day Pacific Northwest rain as the ultimate test.

I can't find any instructions from Lewmar online. Has everyone who has removed and refitted the black gasket has to use sealant to retain it?

[lazybone]

I haven't had your exact problem but I have noticed that port gaskets shrink over time.  That's what might have caused the original leak and the difficulty reinstalling.

[Ron Hill]

John : I believe that you need to relook on line as the replacement gaskets come with a complete set of lewmar instructions. 

[John Langford]

I sure do need to think of something innovative. When I went back to the boat after three days of rain the port had leaked again. there was still water left in the lower fitting into which you turn the locking handle. But when I took the locking handle apart, the fitting was dry and the O-ring was proud of the port lens, and there was no o sign of water anywhere else around the hatch frame. So I dried it out and sprayed it hard with water for 20 minutes. No leaks. This is getting spooky. We have since had two more days of heavy rain and I wonder if the port will have leaked again. Ain't boats intriguing?

[Roc]

John,,
Any possibility that it could be condensation?

[mark_53]

Get yourself a boat cover.  Sounds like the leak can be coming from another source.  You can pick up a tarp and bungee setup for about $20.

[Steve W10]

John, I had the exact same scenario on my aft-most port-side Lewmar.

If this is the Porthole you have.... then here are the installation instructions for the new gasket..... (see two attachments).

I found replacing these gaskets quite a pain and would never think to re-install an old one, regardless of its condition.  They are too inexpensive to take the chance.  I think I paid < $15 each from Defender.

Good luck,

Steve

[added to tech wiki - Stu  3/12/14]

[John Langford]

Thanks everyone for the suggestions, although I am sure that Mark's was intended to be humorous. A tarp and bungee cords would hardly be Bristol fashion bashing to windward on a starboard tack. Steve's attachment of instructions for replacing the gasket is most helpful and should possibly be added to our online collection of manuals/instructions. Thanks Steve. I lucky had done more or less what the instructions said I should do.

The story progresses. I backed out one of the bolts securing the bottom of the inner frame to the bottom of the outer frame and water came dribbling out. It must also have been coming out of what appear to be drain holes in the outer frame which lead into the bottom half of each of the two locking mechanism. As you can see from Steve's attachment, there is an internal  channel all the way around the outer frame. I guess the leak didn't show up when I was running water over the port as the intruding water had to  rise to the level of the lower bolts and the drain holes before it began to leak into the cabin. That obviously takes more than the twenty minutes I poured water but less than all night...the length of some of our recent rain storms.

But how does water get into that internal channel? From Steve's attachment I am guessing that water can only get in through the horizontal joints on each side of the outer frame. I don't think a leak in the connection between the frame and the side of the cabin would do it because the internal channel is not open to the outside. I will look more closely at those joints and for postings on that possibility, but would welcome further comments on my analysis.

[Jack Hutteball]

John,

The port on our 2001 C34 is slightly different than yours, with the joint on the long side rather than the short sides like yours.  I had a leak and checked everything, gaskets etc to no avail.  Under close inspection I noticed that the sealant in the joint had a small almost pinhole opening in it.  I cut out all the existing joint sealant and replaced it with silicone.  No more leaks on that port.  All the rest of mine are still doing fine.

Jack

[Ken Juul]

I don't think the groove is for drainage.  I think it is for sealant.  Buytle tape is perfect for this seal, it doesn't squeeze out like silicone or try to run to the bottom edge.  Check the gaps on the sides, may need a bit extra tape if they look suspect.

[John Langford]

Jack,
I am pretty sure now (by process of elimination) that the leak I am experience in two starboard side ports (the side most exposed to the sun) is coming from the spacers on the two vertical sides of the frame. When you cut out that spacer material on the outside frame did you have any concern that the integrity and shape of the frame would be compromised? That spacer appears to be part of the structure of the outer frame and I wondered about destabilizing it by replacing the hard spacer with flexible sealant. It seems an unwarranted concern possibly because the frame is bolted on and further held in place by sealant. Any thoughts?

[Jack Hutteball]

John, I did not remove the port from the cabin side at all.  I simply cut out the material with a very sharp blade.  Once the main piece came out I was able to remove material back inside the edges of the opening as well with an open paper clip.  I placed tape all around the opening and forced silicone into the opening so that it flowed back into the frame on both sides.  I finished it flush with the outside with a putty knife and let it set up before I removed the tape.  The tape kept me from having to cleanup any silicone on the frame.  The repaired unit looks just like the others, plus no more leaks.  As I noted, my ports only have 1 seam which is located on the bottom edge of the port, so it may be less of a structural issue than yours.  In fact, I don't think my port joint was a hard spacer.  My port is on the side that is also mostly exposed to the sun.  With your port out of the boat can you pull the halves apart and reseal around the hard spacers?

Jack

[Stu Jackson]

Steve's attachment of instructions for replacing the gasket is most helpful and should possibly be added to our online collection of manuals/instructions.

Good idea, thanks John, done, it's under Leaks on the C34 Tech wiki page.