Bottom drain vs EPDM

[EVMIII]

History:

I installed my bottom drain bottom flange and piping several months ago. Weather and life delayed my progress for several months, some how the gasket on top of he bottom flange was damaged. I attempted to install using silicone to provide the seal and fill in the gaps. Didn't work. Filled pond, watched water relatively quickly go from in pond liner to under the pond liner.

Today:

Drained pond, removed top flange of bottom drain. To make matters worse, the liner seems to have torn slightly making the whole a litter bigger than needed. Now what?

My idea, remove all remaining gasket and silicone from bottom flange. Make a new gasket with extra EPDM liner, glue securely to flange. Good bead of silicone, liner, top flange. All easy enough, my problem is the irregular hole in the liner that is slightly larger than needed. How can I do this without having a wrinkle in the liner? How can I get a good seal?

Do I need to patch the hole and start over? My concern with the approach is after patched I need to cut out most of what I just patched and I'm afraid I'd weaken the area. With a great deal of effort I might be able to move the liner enough to make new hole and avoid the recently patched area ( this would create a few other problems itch alignment but if its my only option).

I'm looking for any better ideas or how to make this idea more effective. Any help will be greatly appreciated. If I sound desperate its only because I am. Thanks. Bud

 

[Mucky_Waters]

Detailed pictures with arrows pointing to the torn liner and broken gasket area would be extremely helpful.
If you think it's hard for you to figure out what to do next, how much harder for those of us who can't see the problem with our own eyes.

One suggestion I can make is, whatever repair you do make, DO NOT, fill the pond up, just fill it up enough to see if it leaks again.

 

[EVMIII]

As soon as I can evacuate all the water I'll take some pictures. All you could see now is some muddy water from underneath the liber (not to be confused with Mucky Waters). Hopefully the weather will cooperate. Thanks for the reply.

 

[Catfishnut]

EVMIII,

Although I do not have any experience with pond liners, I do have a suggestion for you. Instead of using silicone sealant, please look into 3M PolyUrethane 5200 Marine Adhesive for making your repairs.
This adhesive is designed for above and BELOW water use, unlike silicone which is not recommended for below water applications.

You can get it reasonably cheap at Jamestown Distributors on line. It was just on sale recently as a matter of fact. I bought four 10oz caulking gun sized tubes for about $61 total including SH and taxes.

It requires a long time to fully cure, though. Seven days! But it adheres PERMANENTLY to most everything and remains flexible.

Thought you might be interested so I dropped this info here for you. Good luck on your repair.

Catfishnut

 

[addy1]

I have used that stuff, it works great, does take a long time to cure. They use it to repair holes in boats

 

[pond maven]

I have used it also. Great stuff, seals leaks wonderfully, but oh so messy. Maybe it is just me, but I get it everywhere. Addy knew at a glance I had been working on my pond when I was out at her place.

 

[addy1]

I have used it also. Great stuff, seals leaks wonderfully, but oh so messy. Maybe it is just me, but I get it everywhere. Addy knew at a glance I had been working on my pond when I was out at her place.

lol you had it on your hands.

I use the pl roofing goop more than anything. I put a hole through the side the 1000 gallon tank with my back hoe, about 2 feet down. Took some of the pl stuff, a piece of liner, gooped it well on the inside and outside. I then stuck the liner over the goop and hole, still holding well, been frozen, smacked a few times with my bucket and still going strong.

The tank has held its level all winter.

 

[HTH]

A friend purchased a 10x50 foot liner and we cut it and spliced it back together to make a 20x25 foot liner with no problems. The key is to get the liner flat when you work on it. A driveway is a good choice.

We purchased the prep and glue/solvent from the same roofing place where we purchased the liner. It was what the manufacturer recommended.

I do not know if you can get it in anything smaller then a gallon can.

 

[EVMIII]

Thanks to all for the comments. I am very familiar with 3M 5200 from my boating days, my concern with using it on the pond is the permanance. I have no doubt it will bond and seal but if I ever needed to work on it again it would be problamiatic (i.e. grinders, etc..). I could use the 5200 to affix the liner to the botton falnge, not sure I'd want to use to seal the top flange down. Of course, any bond that worked would bring with it the same concerns. For those that have used the 5200, how did you use it?

 

[addy1]

I used it to seal a hole I put in the bog, pipe hole, then changed mind. Never has leaked. Since it was going to be under a ton of pea gravel, water, I skipped my fav fix the pl stuff

 

[Catfishnut]

EVMIII,

I have been constructing my filter tank array for my 1,000 gal fishing bait tank. I am using a number of 55 gallon HDPE barrrels that I got for free. I used the 5200 to seal all the fittings going through the side walls and bottoms of the HDPE barrels. Not many adhesives attach to HDPE plastic, but I found this one to work very well. I wanted something permanent, this is listed to be so. I wanted something that would remain flexible, this is it. I'd say it is the perfect adhesive for all pond related items among many, many others! I found out about it while researching how to adhere and seal HDPE and PVC to HDPE plastic. I am using it for all sorts of other applications now, even though it is more expensive than just silicone, etc. Once I have an open tube, I use it up on all my other projects to avoid any waste.

Catfishnut

 

[EVMIII]

I got a lot of the water off this afternoon, still can't get a good picture. My gasket is coated with mud. Any tricks for cleaning the gasket? I'm still thinking I'm going to have to scrape the old gasket off entirely. Is their a better gasket material than another piece of the EPDM liner?

Best idea I have so far is using the 5200 to securely affix the new homemade gasket to the bottom flange. Once cured, use more 5200 to affix the liner to the gasket/flange. A dab of silicone over the screw holes and affix the top flange. Not supposed to rain until Thursday so I hope to attack this task Wednesday after work.

Better ideas and tips still very welcome, you have been very helpful helping me get my head around this project.

 

[EVMIII]

Update:

Scraped old gasket completely off and cleaned
Made a new gasket out of excess EPDM liner (cleaned thoroughly)
Applied 3M 5200 (quick cure) to gasket and flange, pressed with roller
Let set overnight ( snug in 15 minutes, completely set in 24 hours)
Inspected, looked good

Cleaned liner around hole
Used nails to find holes in flange and align liner and gasket
Applied 3M 5200 to top of gasket and bottom of liner
Pressed on liner to gasket

Let set overnight
Inspected, everything looked good
Removed nails and added thick bead of silicone around top of liner though holes
Added top flange, secured, added dab of silicone on top of each screw

After just over 24 hours we got a good downpour dumping about 6 inches of water in the pond
Checked water level after 24 hours, no drop in water level
Rechecked today after 24 more hours, no drop in water level

If all is good tomorrow morning, in stretching out wrinkles and filling he pond.

Thanks to all for the advice, great call on 3M 5200.

 

[Catfishnut]

EVMIII,

Awesome job on the repair! Glad that the 3M 5200 worked well, I knew it would.

Catfishnut

 

[addy1]

Glad it worked for you!