Question about pool leak

[frank1234]

Hi I read these board quite often but have never posted. I am hoping someone can help with a leak I have in my pool.
It is a 38 x 16 inground Vinyl liner with one main drain. The pool looses about a 1/2 inch per day. Last year we had a diver come out and he could not locate the leak. After he dove he plugged the main drain and it continued to leak. We decided to have the Liner replaced since it was very faded and brittle.
The pool continued to loose water with the new liner. Over the winter I let the pool continue to loose water while covered untill it went past the light. at that point I had to fill the pool to make sure we did not damage the new liner. I am now assuming the the leak must be in the main drain.
I am going to swim down and plug the main drain tonight, my question is if I plug the Drain and the pool continues to leak can I be reasonably certain that it is not the Main and something in the shell?

 

[cj3737]

I would do a thorough insp of the liner as well.. he may have missed something... Check any sharpish bend areas... Also around your skimmers/returns

 

[camueller]

if you've let it drain down past the light and that didn't stop it, and plugging up the drain altogether doesn't stop/slow it, then I'd say it is reasonable to assume the leak is somewhere between the light and the drain, in the liner. But that seems unlikely since it happened with both the old and new liner.

How long are you running your pump per day? Is there any leaking going on around the plumbing that you can see?

 

[frank1234]

Thanks for your replies

I searched the liner for holes and I noticed that at the bottom of the stairs the gasket must not have been put on correctly. Right under the bottom molding I can see the gasket must have fallen down befor it was attached. You can see the outline of the the last 5 or 6 of inches of the gasket in the liner and it is somewhat discolored. I did a dye test and did not see a leak there but to be honest I am not sure I am doing the test properly.

has anyone seen some thing like this if I drain the pool to reattach it it would leave only about 3 or 4 inches of water. And I am not even sure I know how to fix.

 

[Vickery]

Vinyl repairs can be performed under water. Vinyl cement is not affected by the water, other than the temperature - colder takes longer, hot may be too fast. The most difficult part is getting to the area and staying down long enough to smooth the patch out so that it looks good.

 

[frank1234]

Vinyl repairs can be performed under water. Vinyl cement is not affected by the water, other than the temperature - colder takes longer, hot may be too fast. The most difficult part is getting to the area and staying down long enough to smooth the patch out so that it looks good.

Thanls, but in this case I don't think i need to repair the vinyl liner I think the problem may be in the gasket behind the liner at the steps