Hi all,
A few months ago I was brushing my pool when I hit the main drain cover pretty good. A few days later I noticed how much the pool had lost water and quickly found the leak down at the main drain. One of the screws that screws the gasket down to the main drain pot had come a bit loose. I then found out that the wrong screws were used when the liner was installed last year. Apparently, instead of using the typical Hayward screws that come with, the installer used a different set that had a smaller diameter but was longer. 3 out of the 8 were stripped and just spinning in place. Under one of these screws was where the leak was. I went ahead and replaced the 3 that were stripped with the correct Hayward SPX1039Z18 screws. I left the other 5 alone because they weren't stripped. I also put a bunch of Permanent Sealer on the screw before putting them back in. The screw with the leak still felt a bit stripped as it wasn't catching very well (better than before though), but the leak had stopped. So I didn't mess with it any more. One of the other new screws was also not catching well, but there was no leak there, so I left it alone. The third new screw was catching just fine.
All was good and the leak had stopped. Unfortunately, today I had a company close my pool up. When they blew out the water in the main drain, the amount of pressure seemed pretty intense. I was immediately concerned that it caused the leak to come back. After they left, I put some painters tape on the liner to mark the water level. 3 hours later, I had lost 1/2" of water. Even though it was only 55 degrees out, I went ahead and jumped in the pool. I took the main drain cover off and confirmed that the leak was back with some dye. This time, it's not leaking under the same screw, but it's leaking under one of the other 2 screws that I replaced because it was stripped.
I took the screw out, put on more Permanent Sealer and put it back in, but no luck.
What should I do at this point? I called the company that closed the pool and they suggested I try adding some sealer around the inside of the gasket and see if that helps. I was trying to think of some alternatives though. I could possibly drain the pool and have an entire new main drain pot put in. But the company I was working with didn't think they would be able to reuse the same liner and thought I would need a new one. I don't really want to have to replace a liner that is only one year old.
Should I look at getting a larger screw? I was thinking of maybe going back to the old "wrong" screw that was used. It's smaller in diameter but it's longer. I could wrap it in Teflon Tape and see if that works. If not, it looks like the SPX1039Z18 screws are just a #10 screw. So maybe I just find another #10 screw stainless steel screw that's just a little longer at my local hardware store? Or perhaps I go up to a #12 screw? I'm just concerned about using too large of a screw and cracking something. But right now I'm losing water at a rate of 4" a day. So if I can't fix the leak, attempting something that might crack the pot probably won't matter.
Lastly, I plan to call the original liner installer to see why they used the screws that they did, but it was an awful experience working with him. I doubt he will pick up the phone or call me back, so might not get anywhere there.
Here is what I'm talking about. The leak is either between the liner and bottom gasket or between the bottom gasket and the "body." I can't get a good look down there to see.

A few months ago I was brushing my pool when I hit the main drain cover pretty good. A few days later I noticed how much the pool had lost water and quickly found the leak down at the main drain. One of the screws that screws the gasket down to the main drain pot had come a bit loose. I then found out that the wrong screws were used when the liner was installed last year. Apparently, instead of using the typical Hayward screws that come with, the installer used a different set that had a smaller diameter but was longer. 3 out of the 8 were stripped and just spinning in place. Under one of these screws was where the leak was. I went ahead and replaced the 3 that were stripped with the correct Hayward SPX1039Z18 screws. I left the other 5 alone because they weren't stripped. I also put a bunch of Permanent Sealer on the screw before putting them back in. The screw with the leak still felt a bit stripped as it wasn't catching very well (better than before though), but the leak had stopped. So I didn't mess with it any more. One of the other new screws was also not catching well, but there was no leak there, so I left it alone. The third new screw was catching just fine.
All was good and the leak had stopped. Unfortunately, today I had a company close my pool up. When they blew out the water in the main drain, the amount of pressure seemed pretty intense. I was immediately concerned that it caused the leak to come back. After they left, I put some painters tape on the liner to mark the water level. 3 hours later, I had lost 1/2" of water. Even though it was only 55 degrees out, I went ahead and jumped in the pool. I took the main drain cover off and confirmed that the leak was back with some dye. This time, it's not leaking under the same screw, but it's leaking under one of the other 2 screws that I replaced because it was stripped.
I took the screw out, put on more Permanent Sealer and put it back in, but no luck.
What should I do at this point? I called the company that closed the pool and they suggested I try adding some sealer around the inside of the gasket and see if that helps. I was trying to think of some alternatives though. I could possibly drain the pool and have an entire new main drain pot put in. But the company I was working with didn't think they would be able to reuse the same liner and thought I would need a new one. I don't really want to have to replace a liner that is only one year old.
Should I look at getting a larger screw? I was thinking of maybe going back to the old "wrong" screw that was used. It's smaller in diameter but it's longer. I could wrap it in Teflon Tape and see if that works. If not, it looks like the SPX1039Z18 screws are just a #10 screw. So maybe I just find another #10 screw stainless steel screw that's just a little longer at my local hardware store? Or perhaps I go up to a #12 screw? I'm just concerned about using too large of a screw and cracking something. But right now I'm losing water at a rate of 4" a day. So if I can't fix the leak, attempting something that might crack the pot probably won't matter.
Lastly, I plan to call the original liner installer to see why they used the screws that they did, but it was an awful experience working with him. I doubt he will pick up the phone or call me back, so might not get anywhere there.
Here is what I'm talking about. The leak is either between the liner and bottom gasket or between the bottom gasket and the "body." I can't get a good look down there to see.
