Fixing corrosion holes in my 1997 Monark Pro 1700

[san dimas]

Hello everyone. I bought a 17" Monark on Thanksgiving day. I finally got around to putting it in the water and checking for leaks. In half as hour it probably took on 3 gallons of water. I took it home to investigate and found some small paint blisters on the starboard side where the side wraps under the bottom of the hull and is rivited. I started to clean the blisters and found a series of about 10 holes in the aluminum over a length of about 3'. Some of the largest holes are almost .5" in diameter! Behind the holes there seams to be the other sheet of aluminum so I guess the water is running in between the 2 sheets of aluminum. I cleaned the paint off using an air grinder and Scotchbright pads so now it is clean. Do you think I can patch these holes with JB Weld and then go over that with Gluvit followed by Rustoleum? If not then I will have to tear out the carpeted wood panels and try and get to the area from inside the boat which I'm trying to avoid. The holes are about 1/2 way between the bow and stern. Other than this, it is really a nice boat and I want save it. Thanks for your help.

 

[Bondo]

Re: Fixing corrosion holes in my 1997 Monark Pro 1700

Ayuh,.... 1/2 Inch holes,..??? Pictures,.... Gotta have Pictures,....

 

[jigngrub]

Re: Fixing corrosion holes in my 1997 Monark Pro 1700

Fill your bilge with water from a garden hose to find exactly where the leaks are.

If the holes you speak of are the sources of the leaks use Loc-tite marine epoxy to fill them over, paint and forget it.

Gluvit goes on the inside of a boat, it's a runny drippy mess on the outside.

 

[san dimas]

Re: Fixing corrosion holes in my 1997 Monark Pro 1700

I'll try and post some pictures.

 

[san dimas]

Re: Fixing corrosion holes in my 1997 Monark Pro 1700

 

[san dimas]

Re: Fixing corrosion holes in my 1997 Monark Pro 1700

I used the garden hose, that's how I found the blistered paint with the holes.

 

[Fleetwin]

Re: Fixing corrosion holes in my 1997 Monark Pro 1700

Yikes! Don't mean to scare you but that boat has seen some serious galvanic action. It must have been moored in a very hot (electrically) marina or somebody has grounded something to the hull. Do not ground any components to the hull.

I would be looking other places, on the hull, for similar situations.

I agree that 2 part marine epoxy can be used. Backing it up with Gluv It, on the inside, would be a good plan.

 

[san dimas]

Re: Fixing corrosion holes in my 1997 Monark Pro 1700

The guy I bought the boat from of course said it had absolutely no leaks. I'm fairly new to boating and I'm learning lessons the hard way Do you think if I put the JBweld with Gluvit painted on top of it that it would work? I've used gluvit before and I understand how runny and slow drying it is. I thought that if I painted it on thinly with a brush it might help seal the hole along with the JBweld. My other concern is that this corrosion will continue to eat at other spots. The rest of the hull looks fine. For some reason it is just this one section of the hull that is corroding.

 

[jbcurt00]

Re: Fixing corrosion holes in my 1997 Monark Pro 1700

It looks like the corrosion is thru to the other sheet of metal too:

And does seem to be fairly extensive:

You should really try & find the interior side of that damage to confirm it's isolated & filling the holes on the exterior will be sufficient.....

 

[san dimas]

Re: Fixing corrosion holes in my 1997 Monark Pro 1700

I was afraid of that. I guess I'll have to figure out how to remove the carpeted wood so that I can see this joint from inside the boat.

 

[lokonn]

Re: Fixing corrosion holes in my 1997 Monark Pro 1700

Wow! People that sell problems like this should be strung up. You are in the right place though. The iboaters here have seen a lot. Good luck and will be tagging along.

 

[Woodonglass]

Re: Fixing corrosion holes in my 1997 Monark Pro 1700

I'd recommend checking into the PC-11 Marine Epoxy. It's some very good stuff and will fix those holes very effectively. You can go exploring if you want, but if this repair stops the water intrusion, then I don't see the point, but Hey, I'm just an Old Dumb Okie and a Glasser to Boot!!!

 

[gm280]

Re: Fixing corrosion holes in my 1997 Monark Pro 1700

If there is that much deterioration on that length of metal now, I would think there is going to be other holes that crop up soon also. It really looks like that entire piece is got some serious corrosion issues. And it looks like the corrosion issue are from the inside. You can try the fixes suggested above and may not have any other issues. But don't be surprised if others show up either. The Marine Epoxy Woodonglass suggested would be a good start and just watch that area real close in the future until you are assured there are no further problems.

 

[fishrdan]

Re: Fixing corrosion holes in my 1997 Monark Pro 1700

Was (is) there a battery located above that corrosion, battery acid will eat aluminum fairly well....

I'd be looking into a mechanical patch, instead of epoxy/JBweld, etc.

 

[san dimas]

Re: Fixing corrosion holes in my 1997 Monark Pro 1700

I think at this point I'm going to take woodonglas' suggestion and fill the holes with PC-11. I like the fact that it's not supposed to sag when applying to over head positions. My feeling is that I have nothing to lose. I really like this boat and would like to get a few years out of it. I'll keep an eye on it for more leaks as time goes on. There are no batteries near the rot. I don't know if the PO used it in salt water or used the hull as part of the electrical system. I'm only going to use it in fresh water.

 

[jbcurt00]

Re: Fixing corrosion holes in my 1997 Monark Pro 1700

Just be certain that the corrosion isn't worse then you think along that riveted seam. An affected area 3ft long sounds significant along a chine where 2 adjacent sections of the hull are riveted together.

 

[Woodonglass]

Re: Fixing corrosion holes in my 1997 Monark Pro 1700

I'd use a punch and do some tapping and poking all along that area to ensure I got all the soft spots discovered. If I found additional ones, I'd drill em out and fill em while I had it bare and prepped. Once filled I'd prep and prime with Self etching primer and then paint with Rustoleum and the added hardener and then go enjoy the boat. I'd bet it would last for a long time. If other areas came to the surface I'd deal with them in the same way. But again, I've never owned a TIN CAN so What do I KNOW!!!!

 

[san dimas]

Re: Fixing corrosion holes in my 1997 Monark Pro 1700

I poked around the area with a cernter punch and everywhere else seems pretty solid. I also strippped the paint back another foot or so beyond the bad area and it seams OK. If I start getting more and more holes, then I will deal with it in a more drastic way. These Monark boats seem to be well made so it's a shame it wasn't taken better care of:blue:

 

[DeepBlue2010]

Re: Fixing corrosion holes in my 1997 Monark Pro 1700

I would start by searching the boat for metal objects that maybe hiding beneath deck. Fish hooks, Lead sinkers, Pennies - especially Pennies - or any other copper made objects). What about your anodes?! Are they in place? Corrosion has a reason, try to find it first or it will continue to damage around your “fix”.
I support the mechanical patch approach; I will not trust epoxy to substitute for metal especially around rivets holes. I am not claiming this is the “right” way to do it; it is simply the way I would do it if I were in your shoes.

 

[Fleetwin]

Re: Fixing corrosion holes in my 1997 Monark Pro 1700

I really think you need to look on the inside. Removing panels is not that difficult. You may have to chip aways some foam.

Make sure NOTHNG is grounded (electrically) to the hull.