Deck leaks on Marlow Hunter 37/40

[Juice6576]

I have a leak on the side decks of My 2015 MH-37 that we bought new. Been fighting to get these fixed for a couple of years with dealer. First attempt made the port side better, but resulted in worse leaks on starboard side. They tried removing and rebedding the fixed cabin ports. Has anyone else experienced this with a late model Marlow-Hunter and have a success story to share.

 

[Juice6576]

Another view, showing the water running back to the aft bulkhead above the galley.

 

[Benny17441]

Production Boats are not known for consistent quality so chances are that another boat may have a different kind of problems than yours. Ours came with thin spots in the cockpit fiberglass that eventually turned into holes. We discovered after five years that the emergency manual gusher pump had been crushed during installation and would have been inoperative in case of emergency. Our 32' boat came equipped with a headsail furler rated at maximum for a 30' boat. Some designer may have decided that with a small headsail it would be adequate as well as cheaper but for us it resulted in a broken tack ring. The furler manufacturer replaced the unit with a beefed up one they had already developed but no one offered to cover the riggin costs. And the list goes on. We are partly to blame because we want a boat with all the bells and whistles at a bargain price and that is what the production boat manufacturers deliver. Labor is not paid well and it shows in lack of care, costly mistakes are hidden rather than fixed and to get them to make good on the warrantee requires a miracle worker. But all in all if they were not around we probably could not afford the boat we have.

 

[dakno]

If you have a 32' boat with a fractional rig then you may be able to use a shorter fuller foil, say for a 30' full rig.

 

[SEMPERAVANTI41]

From your pictures of the leak, the leak appears to be above the level of the fixed cabin ports. If this is true, I don't see how re-bedding them would help. Have you tried after the boat is totally dry spraying water in specific areas to localize the location of the leak? Have you taken down the headliner to help find the source of the leak?

 

[seadaddler]

Water leaks travel all over and as said see if you can take things apart to find your leak
and have some one top side with garden hose and you watch below for leak or get one of those smartphone long snake camera and use it up in those hard to get area and do same with garden hoses.
Nick

 

[richk]

Haven't had leaks like that on our MH37. The mast step/compression post join leaked after acceptance of the boat. Dealer pulled mast, sealed, then restepped. No problems since. Did you look at that? Does compression post show any sign of rust below the head liner?

 

[Juice6576]

Dealership is coming up to start disassembly at end of month. We'll see what they find. I don't want to take any thing a part as long as the dealer is honoring the warranty.

 

[SEMPERAVANTI41]

Juice, I can understand not wanting to take the boat apart. But if you can help to localize the problem, I think you have a better chance of a lasting fix.

 

[kloudie1]

The electric leaf blower and soapy water trick may be indicated for finding this one.. Non invasive and accurate..
Shut all hatches, ports, vents, etc. in the companionway, make one of the washboards of cardboard with a hole in it to match the blower outlet.. Mix up some soapy water to make bubbles.. apply blower to the cardboard hole and paint/spritz the soapy water over the cabin top and fixed ports and all penetrations.. Look for bubbles caused by the escaping air. That way, you can point the dealer to the suspected areas and possibly avoid a lot of de-construction.

 

[lemoiney]

Juice6576, I'm having exactly the same problems. I took possession of my MH37 in June 2015 and have experienced leaks from the fixed side windows since 2016. Minor at first, then more pronounced in 2017. I noticed that the caulking had split in the gaps between the window panels on both port and starboard. I'm guessing because of excessive window contraction beyond the sealant / bedding material's capability to stretch, opening up too large of a gap, when the weather here in Ontario drops to -5F or lower. I cut out much of the sealant/bedding in July 2017 and refilled, but did not remove and re-seat the windows. This helped for the balance of 2017, but the leaks have returned.

Was your dealer or you able to solve your problem? What have you done or tried? I'm about to pull the windows and re-bed entirely in the spring so any advice / experience is appreciated.

 

[Boomer54]

I had similar leak on port side. I also noticed the same caulking issue as lemoiney above. I used a hose, tape and cardboard to isolate the leaking area and it was indeed the fixed port light. I used Captain Tolleys Penetrating Crack Sealer (gotta love the name) and it worked.

 

[lemoiney]

I have a leak on the side decks of My 2015 MH-37 that we bought new. Been fighting to get these fixed for a couple of years with dealer. First attempt made the port side better, but resulted in worse leaks on starboard side. They tried removing and rebedding the fixed cabin ports. Has anyone else experienced this with a late model Marlow-Hunter and have a success story to share.
View attachment 146868

MH has informed me that the original 2014/15 MH37 fixed port lights were bedded using Sikaflex 295UV, which is prone to separation and cracking due to expansion and contraction of the acrylic windows. They now use and recommend 3M 4000UV. Unfortunately, the fix is to remove the windows and manually scrap the old sealant off mechanically, sand and apply the new sealant. The screws are a must and hold the windows in place while curing and maintain the curvature in the windows against the cabin top. MH does not recommend using VHB or removing the screws. The holes in the acrylic for the screws are drilled over-sized, so expansion shouldn't cause a problem. Be sure the screw holes are well sealed. Do not over tighten the screws or you risk cracking the acrylic over time.

 

[SAGE2016]

I have a leak on the side decks of My 2015 MH-37 that we bought new. Been fighting to get these fixed for a couple of years with dealer. First attempt made the port side better, but resulted in worse leaks on starboard side. They tried removing and rebedding the fixed cabin ports. Has anyone else experienced this with a late model Marlow-Hunter and have a success story to share.
View attachment 146868

 

[SAGE2016]

We have a 2016 MH40 that we purchased new from Specialty Yachts, Vancouver BC. It has leaked since delivery. Your pictured leak looks exactly like ours. The dealer has been dealing with another leaky MH40 that was built and delivered just before ours. The dealer thinks the leaks (we have on both sides) are coming in the seam between the long, thick plexiglass windows and the deck. They tried re-bedding one section on the other MH40 and it seemed to work, but they fear it may come apart again with expansion/contraction of the black tinted plexiglass that gets hot. My solution was to cover the seam with heavy duty tape, same kind they use to make the water-line stripe on the hull. It seemed to work. But, I have another theory, tht water gets in the dorade vents and pools up in the interstitial space between the top and the lower layer in the cabin top construction. The water can come from rain and someone hosing the deck. This winter I put the caps on those vents, and had the tape on, and no leaks. Still a mystery, but i think between the two, we have a cure. Might switch to white tape next time just to have less heat build-up.

 

[lemoiney]

MH has informed me that the original 2014/15 MH37 fixed port lights were bedded using Sikaflex 295UV, which is prone to separation and cracking due to expansion and contraction of the acrylic windows. They now use and recommend 3M 4000UV. Unfortunately, the fix is to remove the windows and manually scrap the old sealant off mechanically, sand and apply the new sealant. The screws are a must and hold the windows in place while curing and maintain the curvature in the windows against the cabin top. MH does not recommend using VHB or removing the screws. The holes in the acrylic for the screws are drilled over-sized, so expansion shouldn't cause a problem. Be sure the screw holes are well sealed. Do not over tighten the screws or you risk cracking the acrylic over time.

This is an update to the above. Following my post I removed the port side windows and rebed as per MH instructions. It was a big job. The windows virtually peeled off as the caulking seal had almost completely failed. It appeared to me this was because of the primer on the windows and fibreglass failing (drying out). Sanded the windows and port holes clean, rebedded and reinstalled. Problem solved and dry for the full year. Completed the starboard windows prior to launch this spring. The starboard windows had not failed to the same extent as the port ones and were very difficult to remove. Persevered and can say a month later that my bilge is bone dry. . This is a messy and involved job for most and an expensive one if you hire someone.

 

[Juice6576]

Well, I've got a pretty extensive update. After three tries, I decided to have Manitowoc Marina go after the leaks. Here is what they found. The sealant joint failed between the plexiglass and cabin top. The windows would literally peel off without prying. They found several issues. The cabin liner stuck out and had a gap all around. When the seal failed it allowed the water to run straight onto the wood under the side decks. The plexiglass and cabin sides were not properly prepped, which caused the primer to not bond to the surfaces causing the seal to fail. The sealant around the window perimeter was thin and failed and the rubber spacers under the fiberglass didn't allow the sealant to fully spread out and seal the tow surfaces. The repair included sealing the gaps around the window openings with epoxy. All traces of the old primer and sealer were removed, surfaces were cleaned and sanded and the new primer was applied. Smaller spacers were used and the new sealant was applied and window installed. The end result is that this is the first weekend we've spent on the boat which didn't involve staging containers and towels throughout the cabin during a thunderstorm. They are fabricating new wood to install under the side decks as the original wood is hopelessly rotted. Marlow-Hunter was not responsive to the Marina staff, even though they were a small Hunter dealer for several years.

 

[Don Lucas]

Marlow-Hunter was not responsive to the Marina staff, even though they were a small Hunter dealer for several years.

That is the real sad part of the story to me. You got a new boat and had the leaks right at the start and the factory didn't care.

These types of leaks are not acceptable today. My 2001 Hunter 410 will be 20 years old next month and I have pounded it pretty hard. To date it has no leaks!

 

[Bob R.]

I have been following this thread with much interest since Juice6576 first posted it over 2 years ago. I purchased a 2018 MH40 factory direct dealing directly with MH factory personnel. The boat was delivered to my Marina/Boat Yard in Maryland and commissioned by MH factory personnel, no dealer involved. I have not had any leakage from the side deck windows (I hesitate to call them fixed port lights because there is no port frame, only the two long tinted acrylic window strips that cover the window openings). My concern is that the black sealant that was used to seal the windows to the fiberglass side decks has begun to separate and crack. It is especially noticeable in the seam gap between the two window strips. MH gave me spare caulking tubes for the various sealants they used in the boat construction, both interior and exterior, but they did not include the black sealant used for the side deck windows. Lemoiney noted that Sikaflex 295UV was used for his 2014/15 MH37, but was advised by MH that they now use 3M 4000UV. I have not had much success contacting MH recently, but am going to try again to see if they have a record of what sealant was used to install my side deck windows. I do not want to mix sealants and definitely do not want to have to remove the windows if I do not need to. Are there any questions or follow-up anyone would like me to pass on if I am able to reach my contact with MH?

 

[lemoiney]

I have been following this thread with much interest since Juice6576 first posted it over 2 years ago. I purchased a 2018 MH40 factory direct dealing directly with MH factory personnel. The boat was delivered to my Marina/Boat Yard in Maryland and commissioned by MH factory personnel, no dealer involved. I have not had any leakage from the side deck windows (I hesitate to call them fixed port lights because there is no port frame, only the two long tinted acrylic window strips that cover the window openings). My concern is that the black sealant that was used to seal the windows to the fiberglass side decks has begun to separate and crack. It is especially noticeable in the seam gap between the two window strips. MH gave me spare caulking tubes for the various sealants they used in the boat construction, both interior and exterior, but they did not include the black sealant used for the side deck windows. Lemoiney noted that Sikaflex 295UV was used for his 2014/15 MH37, but was advised by MH that they now use 3M 4000UV. I have not had much success contacting MH recently, but am going to try again to see if they have a record of what sealant was used to install my side deck windows. I do not want to mix sealants and definitely do not want to have to remove the windows if I do not need to. Are there any questions or follow-up anyone would like me to pass on if I am able to reach my contact with MH?

Bob R., looks like you have it covered. I've learned a lot about my boat over the past 6 seasons and must say that as time has past I enjoy the boat more each year. Sealing the windows and having a dry bilge has been a game changer as the boat has finally lost that musty moldy smell. Would be nice to have a local dealer or a factory contact (person or process) to get support (paid if required) if needed...so if you can get that information from them and can pass it along that would be great. Last time I reached them, about 1 1/2 years ago, they directed me back to SailboatOwners for parts and support. I was looking for a proprietary part (the popup fuse buttons) for my MH electrical panel, which are different that anything I've been able to source through chandleries or this site and I want the panel to look original. Thanks and good luck. We'll wait to see your update.