Replacing portlights on Yamaha 33

Jan 20, 2017
78
Yamaha 33 Vancouver
Just finished replacing all the portlights on my recently purchased Yamaha 33'. All of the portlights on the port side had been replaced at some point in the last decade, and were replaced with a reasonable amount of care and skill.

However, the starboard side was horrific. Two of the portlights were 35-year-old originals, and as brittle as Graham Crackers, and the other was at least twenty years old. The starboard side portlights were all retained by screws, and glazed with silicone. All of them were cracked around the fasteners, and all of them leaked like mad.

The port side, however, were secured with a 1/2'' VHB, glazed with silicone, and two of them were still doing a fine job of keeping out the elements.

The starboard side portlights fell out as soon as the screws were released, and were positively churning in silicone. Huge blocks of the stuff, in fact. Took me two full days to dig all that crap out.

The port side only needed some coaxing with Marine Debond and a wedge.

The new portlights are Lexan, secured with a 1'' 5952 VHB, and glazed with Dow Corning 795.

If you are thinking of doing this job yourself, I would recommend avoiding screw fastening, as the linear coefficients between the portlights and hull mean that you will be dealing with cracked portlights before very long. I would also recommend Dow 795, as it stays open long enough to correct any mistakes, leaving you with a professional appearance.
 

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Jdub

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Oct 22, 2012
5
Yamaha 30-1 Charleston, SC
Just now finished the same project on my 30. Very similar situation, except both sides of mine were crap. Took me 3 days to dig it all out and refair the surface. I too used VHB and DC 795. Congrats on a hard job well done.
 
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Jan 20, 2017
78
Yamaha 33 Vancouver
Just now finished the same project on my 30. Very similar situation, except both sides of mine were crap. Took me 3 days to dig it all out and refair the surface. I too used VHB and DC 795. Congrats on a hard job well done.
Ah yes, dental surgery is far more enjoyable. By the time I had reached the end of my second full day of scraping silicone, I was almost delirious with annoyance with the past owners who had decided to let the boat fall into disarray. No word of a lie, I was scraping away long, thick sheets of silicone, and marvelling at the stupidity of the person who had put it all in there.
 
Jan 20, 2017
78
Yamaha 33 Vancouver
That's a hard job - Nice work!
Yes, emotionally, it was very taxing, as there is nothing more foul to deal with than old silicone. As well, using VHB 5952 with the large windows on a Yamaha meant that there was no margin for error when the windows were being fitted into place.
 
Aug 27, 2009
43
Yamaha 33 Portland
The silicone is a mess, but nothing compared to the Dow 795. The 795 is the right sealant, but removing it is a sticky tar ball of unmanageable black goo that adheres to everything. I had to re-do one last year and I could never finish cleaning it up.
 
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Aug 30, 2007
13
Yamaha 30 Vancouver, BC
Just finished replacing all the portlights on my recently purchased Yamaha 33'. All of the portlights on the port side had been replaced at some point in the last decade, and were replaced with a reasonable amount of care and skill.

However, the starboard side was horrific. Two of the portlights were 35-year-old originals, and as brittle as Graham Crackers, and the other was at least twenty years old. The starboard side portlights were all retained by screws, and glazed with silicone. All of them were cracked around the fasteners, and all of them leaked like mad.

The port side, however, were secured with a 1/2'' VHB, glazed with silicone, and two of them were still doing a fine job of keeping out the elements.

The starboard side portlights fell out as soon as the screws were released, and were positively churning in silicone. Huge blocks of the stuff, in fact. Took me two full days to dig all that crap out.

The port side only needed some coaxing with Marine Debond and a wedge.

The new portlights are Lexan, secured with a 1'' 5952 VHB, and glazed with Dow Corning 795.

If you are thinking of doing this job yourself, I would recommend avoiding screw fastening, as the linear coefficients between the portlights and hull mean that you will be dealing with cracked portlights before very long. I would also recommend Dow 795, as it stays open long enough to correct any mistakes, leaving you with a professional appearance.
Hi,
Has the job worked. I had a yard do it on our 30 3 yrs ago and they are having to redo due to failure of the seal. Is the 5952 VHB essential, by this I mean can the 795 be used as a setting compound too?
 
Dec 27, 2020
29
Yamaha 30 - Tall Rig Vancouver
Hi,
Has the job worked. I had a yard do it on our 30 3 yrs ago and they are having to redo due to failure of the seal. Is the 5952 VHB essential, by this I mean can the 795 be used as a setting compound too?
Hi John and all,

I'm looking to do my Y30 windows. What thickness of Lexan did you end up using for your replacement and how is it working out?

Thanks,

Peter
 
Nov 21, 2012
587
Yamaha 33 Port Ludlow, WA
I just redid my forward hatch. I used the 3M VHB tape to attach it and caulked it with Dow 795. I'll let you know how it goes.
 
Nov 21, 2012
587
Yamaha 33 Port Ludlow, WA
No, I don't, sorry. I assumed it was Yamaha. There are no identifying marks on it.