Sealing hole in aluminum below waterline

[seabeyond]

Forum knowledge needed...

I have a pod with one of the transom bolt holes that wasn't used. They drilled the hole before noticing they couldn't run a bolt that low into the hull. It leaks very slowly as it's reliant on the bead of sealant between the transom and pod to keep the water out. I'll redo that as it's shot but I'll also plug the hole. It's been like this for a decade (not my ownership) and might not be an issue if it lived on a trailer. Takes a half cup of water an hour I'd say.

So, should I cut a little aluminum square and JB it in place or is that a bad idea?

Also, what product should I use on the seam between the glass transom and aluminum bracket?

Appreciate the insight.

 

[noluck]

tig welder, if you have 1/8" or thicker material to plug

 

[ship happens]

You have a photo?

 

[seabeyond]

 

[seabeyond]

You have a photo?

Only exterior (posted right above now). I didn't stick a camera in there. They also have a anode bolted through the pod that may well leak too.

I can see the slow ingress of water through the intended transom bolt hole. when I opened the hatch and dried off the hole from the inside when it was in the water. The bottom hole they left would have been really tight to access from the pod side too.. Just bad planning.

You can see the rake on these things.

 

[ship happens]

So basically there is a hole for a bolt that was drilled through the transom, and you can't actually fit a bolt through the hole..? And water is in the pod and going into the boat through the hole they drilled for the bolt they never installed..?

 

[seabeyond]

So basically there is a hole for a bolt that was drilled through the transom, and you can't actually fit a bolt through the hole..? And water is in the pod and going into the boat through the hole they drilled for the bolt they never installed..?

Not quite. They drilled holes in the pod before mounting. The transom doesn't have a hole in it. The bottom bolt wouldnt be accessible on the inside of the transom the way it is laid out so they left the bolt out. I just want to seal the hole in the aluminum pod so the water stops leaking between the pod and the exterior of the transom and through the hole, collecting in the aluminum pod. Left to my own resources I'd just JB a 2"x2" square piece of 1/8" over it and move on. Maybe there's a better option.

No luck makes a good point. I thought it would be hard to get a welder to it but it's at the fab shop in a couple weeks anyhow so maybe I'll wait and see if they can sneak in there and tig it.

 

[ship happens]

Ohh I see. The pods must have a complete back on them? Not just a flange

Geeze I dunno how you'd get a tig in there with 2 hands. Would get really hot also and the material will be dirty as hell. However I would ditch those zincs. The engine zincs and the divers dream style with bonding straps should be good enough

I dont see why just epoxy on a plate like you said wouldn't work as long as the material is super dry. It's hacky but I don't know how your gonna have that kind of access to weld it inside. It will cook whatever gel coat is behind it for sure

 

[seabeyond]

Ohh I see. The pods must have a complete back on them? Not just a flange

Geeze I dunno how you'd get a tig in there with 2 hands. Would get really hot also and the material will be dirty as hell. However I would ditch those zincs. The engine zincs and the divers dream style with bonding straps should be good enough

I dont see why just epoxy on a plate like you said would work as long as the material is super dry. It's hacky but I don't know how your gonna have that kind of access to weld it inside. It will cook whatever gel coat is behind it for sure

Noted. I'll brake kleen it first. Then put a blow dryer on it for a while or sneak a little fan in there. Then JB it.

Yeah, the Anodes are super wonky. They thread right through the aluminum so they probably leak too. I'll pull them out and get the shop to patch that.

Thanks for the response.

 

[ship happens]

Noted. I'll brake kleen it first. Then put a blow dryer on it for a while or sneak a little fan in there. Then JB it.

Yeah, the Anodes are super wonky. They thread right through the aluminum so they probably leak too. I'll pull them out and get the shop to patch that.

Thanks for the response.

if you can get a bit of sand paper in there to rough up and clean up the surface should work just fine.

 

[seachicken]

Weld tabs on externally if you need it bonded. Ship is right about the heat, it won't be good. Old aluminum is horrible to TIG, I've never run a spool gun so can't say about that. I think your best bet might be to clean up the outside and get a really nice clean bead of sealant around the perimeter.

 

[Alex_c]

sand er down to bare metal, wipe with acetone, scuff up a piece of aluminum and slap er on there with a big gob of fast cure 5200. Put a piece of tape over it to hold it in place while it cures. That’s my $0.002

 

[ship happens]

Yeah doing the outside bead again definetly a must. It's little funny on this stuff. Take 5200 for example it's a great permenent urathane. The uv just destroys it. Then you get UV stable stuff and it will shrink over time. Same with sika 295uv. I'd still rather use the uv stuff on the topside. It's challenging. I've done it a few different ways and just depends on the boat and what you want as an end result. Usually I just use the UV stuff on the outside and 5200 to bed the flange and the bolts that fasten the pod

And @Alex_c is kinda right. No reason you couldn't mash in a plate with 5200. Probly a better choice of material

 

[Alex_c]

Yeah doing the outside bead again definetly a must. It's little funny on this stuff. Take 5200 for example it's a great permenent urathane. The uv just destroys it. Then you get UV stable stuff and it will shrink over time. Same with sika 295uv. I'd still rather use the uv stuff on the topside. It's challenging. I've done it a few different ways and just depends on the boat and what you want as an end result. Usually I just use the UV stuff on the outside and 5200 to bed the flange and the bolts that fasten the pod

And @Alex_c is kinda right. No reason you couldn't mash in a plate with 5200. Probly a better choice of material

I used the 3M 4000 UV on my trailer and I’m not impressed. Started getting chalky and failing after 2 years. Maybe my expectations are too high. The $10 tubes of DAP urethane or Sika 291 seem to be better value than 4000UV, and seem to be holding up better, although I didn’t use them on the roof. Choosing the correct goo is surprisingly a giant rabbit hole to go down

 

[ship happens]

I used the 3M 4000 UV on my trailer and I’m not impressed. Started getting chalky and failing after 2 years. Maybe my expectations are too high.

Yeah see it's a dart throw. What your describing is how the 5200 or 4200 will end up like exposed to UV. There's not a product that I've found that does it all. The sika 295uv doesn't do that but it will shrink. Will keep it's color, which is nice when caulking in a white pod. (why the **** does everyone want a white pod?) lol

 

[Alex_c]

Yeah see it's a dart throw. What your describing is how the 4200 or 4200 will end up like exposed to UV. There's not a product that I've found that does it all. The sika 295uv doesn't do that but it will shrink. Will keep it's color, which is nice when caulking in a white pod. (why the **** does everyone want a white pod?) lol

yeah I gotta re-do it this year and I’m gonna go with sika or maybe one of those RV roof sealants. It was definitely the 4000UV, but maybe only lasting a couple years is the nature of the beast. Maybe ppl want a white pod because cleaning the boat is one of the cheapest ways you can spend some quality time with her

 

[Brando]

Could you just take a fender washer loaded up with sika and screw into the transom there? It really shouldn’t be leaking if the perimeter is sealed properly..? the zinc holes they can clean a couple inches around each one with a flap disc and ream the hole with a big countersink and plug weld it from the outside.

 

[Captuna]

JB is not affected by uv or shrinkage …I had a mechanic who kept my 1951 BHMS Cummins running, and when he died I had to buy a new engine. Fixes all. Should have eased it on the Challenger. Stronger than aluminum. Have faith.