Sealing compound preferences

I am looking to seal all my hatches and pole holder where it is rivoted and was wondering what is the preferred compound people like the best?

Also has anyone ever decided to fill the cavity with sprayed in foam instead of using noodles?
I was thinking about creating areas inside my kayak and then fill the remaining area with foam and was wondering if this would be a good idea or do you think foam noodles are better.
thanks for any input
JImbo

I'd say goop. In case you ever need to remove the rivet. There has been talk of the expanding foam. One of the main issues is that stuff does absorb water so you'll end up paddling a sponge. Also that stuff produces some serious heat (as it expands/cures) so that may be an issue. Noodles or float bags are you best option

I have used marine goop, and found that to work well.  As for the foam andother issue, forget to remove or plugg something you may never get it off  or on again as that stuff is extremely sticky when setting up. 

 

  Good 'Ol Dap or 3m silicone has worked for me.  (Blue tube)

I'm sold on Marine Goop.

What the kmstorm & EWB said regarding the foam.

Goop or silicone work equally well on rod holders/etc.  Goop remains sticky, while silicone dries and can be peeled off a bit easier if need be.

My P13 has been bugging me since the day I got it due to water in the hull. Not much, but after 4 hours in the salt, about a pint, pint and a  half.

Last month, I got it ready for this year's Bean adventures, so I put it upside down on a couple saw horses in the garage , turned off all the lights, and stuck a  contractors mega watt light in it facing the stern. Found what looked like a pin hole at a scupper hole. Couldn't find my Marine Goop, so grabbed a tube of Lexel and used that. Also found the areas around the 4 screws at the rudder mount had a bit of light emitting, Lexeled them too.

Took it out of Pigeon in a good size swell for about 4 hours, and not a drop of water in the hull. I've checked the Lexel, and this stuff is strong.

Rich

Its probably goop anyway!!

 

  I tried Lexel once.  Found my transducer hanging by a "Lexel thread" Or suspended,by a lexel thread once I got the kayak off the ceiling.  Kayak was suspended to ceiling for storage, and one hot summer day, the lexel got gooey and stretched under the weight of the transducer.  So, now I use silicon.  It "skins over" in 15 minutes, and cures in a few hours, stays flexible and is easy to remove in needed.

An old member named Scwafish turned me on to 3M "5200" - it's good stuff, and I've tested it under the worst conditions - mine!  

http://www.3m.com/product/information/Marine-5200-Adhesive-Sealant.html

An old member named Scwafish turned me on to 3M "5200" - it's good stuff, and I've tested it under the worst conditions - mine!  

http://www.3m.com/product/information/Marine-5200-Adhesive-Sealant.html

I used this in the past but found it takes forever and a day to cure.
Over time it holds up no better or worse than either marine or plumbers goop.
I 5200'd 3 transducers in 3 different kayaks and ended up gooping those 3 later on. That was before I switched to the 'donut' method. Guess what I use to secure that?....Goop