Sealing thru hull hardware

[Husqy510]

We recently rigged a Howard Cat, but held of on mounting the swim steps until we had a chance to float it. Now that we now where we want them mounted we can install them.

What's the best way to seal the area?

Thanks, Ian

 

[420HOA]

Sika flex

 

[renodaytona]

3M 5200 is what I've used.

 

[n2otoofast4u]

I have always used Life Seal.

 

[RiverDave]

3M 5200 is what I've used.

This is what all the shops use out here

 

[Husqy510]

Thanks for the replies. Do I need to treat the bare wood? Or simply use the sealer on the inside and outside

 

[Warlock1]

You can just use it on the outside. Just make sure the entire mounting area is covered. Also there are multiple types of 5200. White or black. Slow dry or fast dry. Make sure you get what you need. Fast dry is about an 8 hour set up, where the slow dry is about 5 days. Once you are done use a plastic scraper and clean up all the stuff that has squeezed out and wipe down with Naptha.

 

[Backlash]

Seal the wood inside your transom as good as you possibly can after you drill the holes. If you skip this step or don't do a good job, you'll be replacing the transom in your boat which is not cheap. Just giving my .02.

 

[Motor Boater]

I like the drill fill drill method. Drill the hole slightly larger than you want it, fill with epoxy to protect the core, drill again and install

 

[wzuber]

Read the product labels
3m 5200 is for permanent installations like deck hardware, underwater running hardware etc. Should you want to remove a bracket in the future you will likely have a gel coat repair to go along with it.

3M 4200 is for removable items such as what your doing.
You can seal transom wood w/ polyester resin thinned 30% w/acetone, double catalyst for resin volumn. The wood will soak it up well. Small artist type paint brush to apply. Mask well for drippy mess.

 

[jmeads]

Read the product labels
3m 5200 is for permanent installations like deck hardware, underwater running hardware etc. Should you want to remove a bracket in the future you will likely have a gel coat repair to go along with it.

3M 4200 is for removable items such as what your doing.
You can seal transom wood w/ polyester resin thinned 30% w/acetone, double catalyst for resin volumn. The wood will soak it up well. Small artist type paint brush to apply. Mask well for drippy mess.

what he said !

 

[Ragged Edge]

Read the product labels
3m 5200 is for permanent installations like deck hardware, underwater running hardware etc. Should you want to remove a bracket in the future you will likely have a gel coat repair to go along with it.

3M 4200 is for removable items such as what your doing.
You can seal transom wood w/ polyester resin thinned 30% w/acetone, double catalyst for resin volumn. The wood will soak it up well. Small artist type paint brush to apply. Mask well for drippy mess.

what he said x2.

 

[Outdrive1]

Seal the hole with resin. Use clear silicon when you install the hardware. 5200 is a mess and it’s permanent.


Sent from my iPhone using Tapatalk

 

[Backlash]

I am not going to use 4200 or 5200 on any of my boats. Every hole in my transom is sleeved with a thick fiberglass tube strictly to protect the core of the transom from water intrusion. It also makes the area where things are installed less prone to flexing when the fasteners are tightened down because of the tube inside. I will be using butyl tape around each hole where a fastener goes. It doesn't leak, has adhesive properties and will remains flexible for decades. Should I need to remove something later on, there wont be any damage to the gelcoat where the tape was used.

 

[Willie B]

3M 5200 is what I've used.

...That is the real deal you’ll get some argument as far as the difficulty of removing something but that is somewhat bullshit I have used it for decades...

 

[D19]

Resin on brush for bare wood. Tape the areas off first to prevent a mess.

Permatex 80855 clear RTV silicone

 

[ka0tyk]

ive used 5200 and regretted it. you could pick up a house with the stuff. if you EVER needed to remove those steps for whatever reason you would need to jackhammer them off.

the point isnt to create a permanent structural bond, its just to keep water out.

just use some regular ol 3m marine grade silicone.

 

[Wizard29]

You might try something called E6000. Home Depot has it. I’ve been using it for years on anything that needs a good adhesive or sealer. It is clear and turns into sort of a rubber when it cures/dries in 5 to 30 minutes (depending on how much you use). You can pull away any excess after it dries that squeezes out after assembly. It is completely hydrophobic and actually repels water. A part installed using this stuff as an adhesive or sealer can be removed without damaging gel coat or other surfaces and removal difficulty depends on the size of the part.

Years ago I was a service tech and worked on very specific machines using high pressure, high temperature water and alkaline chemistries. I used E6000 for repairs and it was also used in certain places during the assembly process. I’ve also used it on my boat, hot rods, offroad cars, and a ton of other stuff.

It works great. Cleanup if you get it on your fingers is blow on it to make it dry and rub your fingers together. It’ll turn into little rubber pieces you can pull on to peel the rest off. Give it a shot and if you don’t like it, peel it off and use something else.

 

[RiverDave]

You might try something called E6000. Home Depot has it. I’ve been using it for years on anything that needs a good adhesive or sealer. It is clear and turns into sort of a rubber when it cures/dries in 5 to 30 minutes (depending on how much you use). You can pull away any excess after it dries that squeezes out after assembly. It is completely hydrophobic and actually repels water. A part installed using this stuff as an adhesive or sealer can be removed without damaging gel coat or other surfaces and removal difficulty depends on the size of the part.

Years ago I was a service tech and worked on very specific machines using high pressure, high temperature water and alkaline chemistries. I used E6000 for repairs and it was also used in certain places during the assembly process. I’ve also used it on my boat, hot rods, offroad cars, and a ton of other stuff.

It works great. Cleanup if you get it on your fingers is blow on it to make it dry and rub your fingers together. It’ll turn into little rubber pieces you can pull on to peel the rest off. Give it a shot and if you don’t like it, peel it off and use something else.

And you say this is good enough for a long term marine installation?

RD

 

[Wizard29]

And you say this is good enough for a long term marine installation?

RD

Yep. I used it on a couple of through-hull bulkhead fittings on my boat when I changed them to stainless units. It’s pretty neat stuff. Durable enough to create a water tight seal between components, but not so aggressive as to be unmanageable if things need to be disassembled.

 

[MK1MOD0]

I like the drill fill drill method. Drill the hole slightly larger than you want it, fill with epoxy to protect the core, drill again and install

After reading this it seems like a great idea. thanks for the tip.

 

[AzMandella]

I'm surprised nobody mentioned Marinetex . Mix it up and put in hole insert bolt while turning . Tighten nut and wipe excess away .

 

[GETBOATS]

Already been mentioned but a BIG NO on 3m 5200, it will remove gel coat if you ever have to remove it, absolutely no need, its like tire rubber. don't use a silicone based product as it promotes corrosion because of the acids in its make up. 3m makes products that offer underwater qualities and so does BoatLife.
but really I've seen outboards installed with 3M 5200 that with all attaching bolts removed would not come loose from the transom.