96' 376 Side window cracked

[varigging]

So I found a crack in the starboard side window of my 1996 - 376. It runs the whole way from top to bottom as seen in the photo. It is interesting because I have recently noticed that there is a hollow space between the two windows that seems to trap a lot of heat and pressure. So much so that it has bulged out the windows on both sides in this area. This is where the crack has occurred. In searching the web and on this site, it seems that this problem has only been reported on the 1996 models. I have talked to the folks at the HunterOwners.com store and they can get me a replacement window made so I can replace it. I was wondering if anyone knows if Hunter modified the 376 in 1997 to address this issue? I was thinking of drilling a small hole on the inside of the cabin to allow heat and pressure to escape this cavity so not to stress the new window. Any thoughts?

 

[Ralph Johnstone]

It runs the whole way from top to bottom as seen in the photo.

Normally, one only sees annoying stars and crazing on aging acrylic windows.

It would be intersting to note (as you're removing the window) if any screws were left in the acrylic window. Hunter often uses screws to hold the windows in place whice the DC 795 is curing. However, if the screws are not removed after the silicone has set, it's a recipe for disaster as the FG cabin and acrylic window expand at different rates.

 

[Allan Frey]

I have a similar vertical crack on my 376, but on the port side. It appears that it occurs where Hunter bent the acrylic to follow the fore/aft curve of the cabin.

"...store and they can get me a replacement window made so I can replace it."
What did they quote as the cost of the acrylic and the shipping cost? Will it have the bend in it?

I was thinking of having a local plastic shop make it or maybe just put in some black Dow 795.

allan

 

[varigging]

They haven't quoted me a price yet. I have to send them the old one first. I figure it will be in the hundreds of dollar range. It will have the bend as well. That is my biggest issue because I don't have an oven large enough to heat the piece to get the bend in it.

The cracking might be caused by opposing forces. The bend going one way and the bulge going the opposite. Hummmm.

 

[reraft]

I have a similar vertical crack on my 376, but on the port side. It appears that it occurs where Hunter bent the acrylic to follow the fore/aft curve of the cabin.

"...store and they can get me a replacement window made so I can replace it."
What did they quote as the cost of the acrylic and the shipping cost? Will it have the bend in it?

I was thinking of having a local plastic shop make it or maybe just put in some black Dow 795.

allan

I had a cracked side window on my 96 376 i the dead space between the two windows - I used a die grinder & cut out the window in the dead space & had an insert piece made & installed it with dow 795 sealant - it now has two vertical seams but is in the dead space so no problem - been great for five years & the piece of plexi was abut $10.00 & a tube of 795

 

[garymckin]

I also have warped areas on both sides of the large side windows but no cracks. I have a 97, 376.
I would like to have pics on the repair work
Gary

 

[Keith in Punta Gorda]

Same issue here, and I believe resolved. I believe the root cause of the problem is that the sidelights are not supposed to be sealed between the openings. In other words there is only supposed to be sealant on the perimeter of the acrylic. What happens if the void is sealed is that moisture gets trapped in the void and when the sun hits it. it expands and stretches the acrylic and weakens it. You will likely see a bulge in the acrylic. The best answer is to use Dow primer (looks like a square pad applicator on a small tube of black ink) on the acrylic on the perimeter and where the void is located to give a visual of a smooth sealant coverage and then only apply the sealant to the perimeter of the acrylic. Good luck.

 

[Allan Frey]

Update on my previous post. I routed the crack into a V shape and squeezed in black Dow 795. It is hardly noticeable. I also put 5 applications of Capt Tolley's creeping crack cure around the periphery of the window, 30 minutes apart. Then smeared in some 795 around the periphery where the original caulk had shrunk and left a fine gap. We've had several heavy rains and there have been no more leaks.

allan

 

[varigging]

Update

So I figured I would post an update. It looks like I am not the only one to have this issue. I see that HO now sells the replacement window for the Starboard side. This happens to be the side I need. So I bit the bullet and ordered one. Once it comes in I will replace mine out and post another update. I am still thinking of putting some type of vent hole in that blank space to cut down on the heat/pressure build up. From my small research this issue seems to be really only on the 1996 models.

 

[Keith in Punta Gorda]

Making replacement lens is easier than you might think. Most glass stores in our area can duplicate the lens if delivered to them or replicate it from a paper tracing of the lens. I made my own both sides from a paper template. When you install yours I strongly suggest that you apply sealant only to the outside perimeter of the hole. Ignore the fact that there is a panel in the middle. That will eliminate the pressure issue. Also use a 3m primer to color in the panel and the entire mounting area. This will eliminate the issue with the visual effect of seeing parts of the gelcoat through the lens. Mine was easy to install and looks and performs well. Don't forget to use spacers to keep the lens from touching the gelcoat.

 

[PAC3142]

Hi, this is good information. Is the procedure for removing and replacing windows documented anywhere? I will need to do this on my 37.5. This should be a FAQ, but I can't find FAQs on this site.

 

[joelvannorsdel]

I have worked with Plexiglass windshields for sailplanes and to stop a crack from growing you drill a small hole at each end to keep it from creeping.

Now for my Hunter 42, I have replaced all the side windows here in California. I found a guy who does all the work and it looks great. So if you need something like this he will come to your boat and measure, then make and install, all very reasonable priced. His contact information is Marco 949-290-1069.

Joel
S/V Alter'Tudes

 

[Keith in Punta Gorda]

It's fairly straightforward to remove. Try to make a tracing before removing in case it breaks. Hardest part is cleaning the adhesive surface. I buy 4x8 sheets of acrylic from Home Depot special order to save shipping. Jig saw cuts to shape. Router is needed for fixed lights. Hatches require plastic drill bits. I make shims /spacers by cutting eighth inch squares of rubber sheet or washers. Epoxy them in first one on each surface. Dry fit. Mark the location. Remove acrylic apply 795 and primer as needed.

 

[varigging]

Keith,
Thanks for the heads up. I think you are exactly right about not sealing the inner dead space. That should le the heat and pressure out and keep the window from cracking.
Where did you get the 3m primer?

Thanks again,

Will

 

[Keith in Punta Gorda]

Just looked at primer. Actually is Dow Betaprime 5504G. I get it in 10ml tubes with an applicator built in from a friend in the autoglass business. I can't seem to find it in this container retail, only in 125 ml bottles. One the plus side the unused primer can be saved. Tubes are single use.

Another thing I found is after the lens is set and the excess adhesive cleaned away and the masking tape removed, wait about 45 minutes and apply a little bit more pressure evenly and overnight to the lens. The adhesive will slightly mound up very slightly and look like factory original. It's a nice touch.

 

[Keith in Punta Gorda]

BTW. Acrylic bends fairly readily to the curve on these port lights. The lens is not curved when supplied. It will easily bend 2 to 3 degrees per foot without any heat.

 

[varigging]

Awesome advice. Thanks again for all the help. I will post photos and an update once I get done.

 

[varigging]

Ready to set

KEITH,
I am just about ready to install my new window.
I have a few questions though.

I have two tubes of 795. How much am I going to need? I really don't want to run out mid install. I was able to get some of the 5504 primer so I am good to go there.

Also how did you keep pressure on the window while it sets up. There aren't any screws to hold it in place.
I was going use small black plastic washers about 1/8 think to keep the gap correct. I figured I would just calk around them, and leave them in place instead of trying to remove them and cause a mess.


As always thanks for the help.

I think the biggest thing is not calking around the inside of the dead space to let air and pressure move in and out. That should stop the cracks from reoccurring.

Thanks agin,
Will

Just looked at primer. Actually is Dow Betaprime 5504G. I get it in 10ml tubes with an applicator built in from a friend in the autoglass business. I can't seem to find it in this container retail, only in 125 ml bottles. One the plus side the unused primer can be saved. Tubes are single use.

Another thing I found is after the lens is set and the excess adhesive cleaned away and the masking tape removed, wait about 45 minutes and apply a little bit more pressure evenly and overnight to the lens. The adhesive will slightly mound up very slightly and look like factory original. It's a nice touch.

 

[Keith in Punta Gorda]

I applied pressure using a 2x4 and a block with some weight on it to hold the fore and aft ends in place. I pivoted the 2x4's against the gunwale and let it lay on the acrylic. A friend used two suction cups from an auto parts store (used to pull dents I think) on the inside and pulled them to things in the boat. I think his looks better but mine was good. Really doesn't need much pressure. Two tubes is more than enough. Think I used one last time.

 

[Keith in Punta Gorda]

Oh and definitely leave shims in.