Transom assembly sealing

[Dude! Sweet!]

I'm about to remount my transom assembly. I have the Merc gasket but have been told to use either 5200 or silicon to make sure it doesn't leak (especially if transom isn't perfectly flat).

What's the consensus preference? 5200 or Silicon?

Thanks!

[Whoz Your Daddy]

5200 wont let you down. Just feel bad for the poor guy who might have to remove it 10 years from now.

[Dude! Sweet!]

5200 wont let you down. Just feel bad for the poor guy who might have to remove it 10 years from now.

Aka "me" and "next year"... ha ha ha.

[Chris]

If you 5200 it, plan on some damage trying to remove it if you ever have a problem.

"If".
I crack myself up.

[rchevelle71]

Isnt there a 4200 which is supposedly removable? Silicone is for fish tanks, I wouldnt use it anywhere on aboat.

[MOBILEMERCMAN]

I would suggest on bravos to use weatherstrip adhesive on the aluminum to seal side and nothing in the paint side. On TRS I would suggest perfect seal on the aluminum to gasket and dry again against the paint. Silicone is not to be used. If the transom is soft or not flat would be the only time to use 4200 or 5200 IMO.

[Dude! Sweet!]

Cool. Thanks guys. Transom's not soft, but not flat either. I'll test fit and see how bad and then either do the adhesive or the 4200/5200 (whatever it takes) depending on how it looks.

If the boat is a "keeper" based on how it runs this year it's going to get new tabs and an uprated transom assy next year. If it doesn't run like we're hoping then it will get a 454 and rear bench seat next year, but keep this transom assy and tabs...

[insanity]

Even 4200 is a pain to remove, something like this might be the ticket:
http://solutions.3m.com/wps/portal/3...beQH8HT14PGTgl

Give it a 'caulk' around the outside of the transom assembly and call it good.

[DAREDEVIL]

Just clean it up nice and use marine grade silicone. It seals nice and comes off easy if needet !!!!!!!!

When i bought my boat they used 5200 and i had to rip off the outside layer of glass, to get the transom and the tabs off !!!!!

Westmarine....marine grade silicone white or clear !!!!! 12 bucks or so...

[TxHawk]

How about trim tab mounts. What is the best method to seal thru bolts. How do you avoid leaks past the head of the bolt/washer without being sloppy with the sealer of choice?

[Trim'd Up]

I usually use life seal and 't haven't had any issues. It isn't a pain to remove like 5200 or 4200 either.

[Geronimo36]

I'm with Jim...... glue the seal onto the assembly with 3M weatherstrip adhesive or bellows adhesive but dry on the boat... If you insist on using sealer use something pliable and non-hardening like perfect seal, form-a-gasket or lifecaulk.

I like to put a little lifecaulk around the base of each stud to provide a little extra protection for the transom wood but dry on the seal. The seal (weather strip) is not meant to be sealed like a thru-hull fitting.. I only use sealer if I'm attempting to re-use the gasket which is almost never!

[Geronimo36]

How about trim tab mounts. What is the best method to seal thru bolts. How do you avoid leaks past the head of the bolt/washer without being sloppy with the sealer of choice?

I have used lifeseal and lifecaulk. Once installed you have to clean with acetone but try not to douse it.


LifeCaulk - "A long lasting, permanently flexible marine polysulfide sealant which can be sanded, painted, and used above and below the waterline. Tack-free in 1 to 3 days, excellent resistance to teak oils, gasoline, and diesel fuel. Ideal for teak decks, to bed deck and hull hardware, seal thru-hull fittings, and underwater seams. Will bond to fiberglass, rubber, metal, glass and itself. Cures to a firm flexible rubber seal with excellent waterproofing and adhesion qualities. Can be applied underwater for emergency repairs. Can be applied to damp surfaces."

LifeSeal - A unique combination of marine silicone and polyurethane, formulated especially for fiberglass. Life Seal® offers a fast-curing, low odor, high adhesion, non-sagging, non-corrosive, non-yellowing formula. It provides a durable permanent watertight seal for joints subject to structural movement. May be used above or below the waterline. Use for sealing decks to hulls, thru-hull fittings, vinyl ports, sealing/glazing windshields and bedding marine hardware. Will adhere to metal, glass, wood, Lexan®, ABS® and certain other materials. Can be removed without damaging gel-coat. Not recommended for ferro cement hulls, impregnated wood or oil-soaked materials. Cures in presence of water. Mildew resistant and acid-free. Custom colors available.

[Seafordguy]

I would suggest on bravos to use weatherstrip adhesive on the aluminum to seal side and nothing in the paint side. .

This was how I did it, and how it was done when I took it apart. I also ran a small bead of caulk around the assembly once it was completely bolted together, as was done before I took them off.

Mine were dry as hell.....

[Dude! Sweet!]

Right on. Thanks guys!

[TxHawk]

I have used lifeseal and lifecaulk. Once installed you have to clean with acetone but try not to douse it.


LifeCaulk - "A long lasting, permanently flexible marine polysulfide sealant which can be sanded, painted, and used above and below the waterline. Tack-free in 1 to 3 days, excellent resistance to teak oils, gasoline, and diesel fuel. Ideal for teak decks, to bed deck and hull hardware, seal thru-hull fittings, and underwater seams. Will bond to fiberglass, rubber, metal, glass and itself. Cures to a firm flexible rubber seal with excellent waterproofing and adhesion qualities. Can be applied underwater for emergency repairs. Can be applied to damp surfaces."

LifeSeal - A unique combination of marine silicone and polyurethane, formulated especially for fiberglass. Life Seal® offers a fast-curing, low odor, high adhesion, non-sagging, non-corrosive, non-yellowing formula. It provides a durable permanent watertight seal for joints subject to structural movement. May be used above or below the waterline. Use for sealing decks to hulls, thru-hull fittings, vinyl ports, sealing/glazing windshields and bedding marine hardware. Will adhere to metal, glass, wood, Lexan®, ABS® and certain other materials. Can be removed without damaging gel-coat. Not recommended for ferro cement hulls, impregnated wood or oil-soaked materials. Cures in presence of water. Mildew resistant and acid-free. Custom colors available.

Thanks, so to clarify, you are using this stuff sparingly and cleaning off the "squeeze?"

[MOBILEMERCMAN]

On the tabs I use 5200 on the bolt holes. Do not use on the plate flat surfaces just in the hole. Use a dummy bolt or something slightly smaller to work the sealant in to the hole. Then apply some to the bolt for assembly. Make an effort not to get it everywhere.

On caulking the transom assemblies I hate to see the caulk on the perimeter. If you want to go the extra mile I suggest using epoxy with a small touch up brush to seal the wood before installation. I also recommend the cut out gets sealed as well.

[2112]

I have used lifeseal and lifecaulk. Once installed you have to clean with acetone but try not to douse it.


LifeCaulk - "A long lasting, permanently flexible marine polysulfide sealant which can be sanded, painted, and used above and below the waterline. Tack-free in 1 to 3 days, excellent resistance to teak oils, gasoline, and diesel fuel. Ideal for teak decks, to bed deck and hull hardware, seal thru-hull fittings, and underwater seams. Will bond to fiberglass, rubber, metal, glass and itself. Cures to a firm flexible rubber seal with excellent waterproofing and adhesion qualities. Can be applied underwater for emergency repairs. Can be applied to damp surfaces."

LifeSeal - A unique combination of marine silicone and polyurethane, formulated especially for fiberglass. Life Seal® offers a fast-curing, low odor, high adhesion, non-sagging, non-corrosive, non-yellowing formula. It provides a durable permanent watertight seal for joints subject to structural movement. May be used above or below the waterline. Use for sealing decks to hulls, thru-hull fittings, vinyl ports, sealing/glazing windshields and bedding marine hardware. Will adhere to metal, glass, wood, Lexan®, ABS® and certain other materials. Can be removed without damaging gel-coat. Not recommended for ferro cement hulls, impregnated wood or oil-soaked materials. Cures in presence of water. Mildew resistant and acid-free. Custom colors available.

Damn, so is one better for this application? seems to me lifeseal might have the edge.

.

[DAREDEVIL]

I actually think that marine silicone is kinda like the lifeseal,,,it does not harden out ....just stops sticking after about 2-5 min.

Very durable, did not have any problem with it at all.

And yes 5200 in the bolt holes on the tabs...i am with jim on that.

STILL MESSY !!!!!!

[Geronimo36]

Damn, so is one better for this application? seems to me lifeseal might have the edge.

.

I like the lifecaulk bedding things like transducers and anything that is going to be painted but lifeseal for the rest!