Sealing Transom Penetrations

[rost495]

Have drain plugs etc... to put back into a poured new transom. Plus adding transducer.

What is best way to seal holes these days? I"m not worried about price so much as I want to do it once and do it right.

Thanks, Jeff

 

[Kevin70]

Re: Sealing Transom Penetrations

3M 5200 for a strong waterproof seal. 3M 4200 for a slightly more pliable caulking. If you want to go "all out", you could drill the holes slightly larger than they need to be, fill that with epoxy that has been thickened to the consistancy of peanut butter, Then drill the smaller hole through the epoxy, and seal up with the 5200. This will last alot longer than you or your boat.d

 

[rost495]

Re: Sealing Transom Penetrations

Epoxy won't mix with seacast. But I do like the idea. May not be needed though.

Let me guess though if I try this, we are talking 1.1/4 inch plugs so drill out next larger drill size probably 1.3/8. Then since resin is compatable with seacast, I can mix with aerosil to a gel and work around in there good. Same results?

OR since there is no wood in the transom just use 1.1/4 and 5200 maybe??

BTW source of either sealer?

 

[studlymandingo]

Re: Sealing Transom Penetrations

From my understanding of the 3M products, the 4000 is what is recommended for fittings that join metal and fiberglass or wood.

 

[epresutti]

Re: Sealing Transom Penetrations

rost495,

I would go with the 5200, just so long as you never want to take it apart, very permanent bond.

Here is the 3m product brochure, hope this helps.

http://multimedia.mmm.com/mws/mediawebserver.dyn?6666660Zjcf6lVs6EVs66SY6HCOrrrrQ-

Peace.

Ed.

 

[sdunt]

Re: Sealing Transom Penetrations

Where many transoms fail is all of the bolt and screw holes in them that allow water in and past any epoxy seal.. One Idea I picked up is to use tubing to seal the holes. My appologies to the original poster that I copied this off of:
"go to good ACE/TRUE VALUE hardware or hobby shop that sells K & S tubing..

buy a piece of tubing with an ID size that is two to three sizes bigger than your bolts.. but is still a common drill bit size on the OD..

bore holes thru the transom and install the tube all the way thru the transom, coat the outside of the tube with epoxy before you install the tube, you want to cement it in place and seal it and the wood you just punched a hole in.

As you install the bolts, shoot caulk/silcone in the tube in between the bolt and the tube to water seal 'the hole in the boat'

the tube isolates/seals/protects from water infusion and isolates it from EVER soakin' into the side walls of your new transom. Kind of like making a drain plug hole but for the motor mounts or any other holes in the transom."