Ancient hydrostatic Sylvan plug stuck.

[aharon]

Hey all, after 10 years with my 1964 Sylvan gunnite pool, I finally decided to open up the hydrostatic vents, because the pool has been creeping above the decking (or the decking has been sinking). I am hoping to see twin geysers of dirty water jetting up as the pool gently sinks back into its cavity. Maybe that is ridiculous but I went ahead and drained the pool, only to find that the ancient plugs resist all my efforts. Lacking a tool that specifically fits into this giant Phillips cross, I have been using a sturdy metal file that fits into one slot, torqued with a heavy plumber's wrench. Thing won't budge, and I'm fearful that the file will jump and strip the slots (the plug is plastic).
I am not sure if the plug has been immobilized by plaster. I'm afraid to chip away at the perimeter of the plug because there is a definite slope of the plaster down to the plug, implying that the concrete is very close to the surface.
Has anyone encountered these plugs before (picture attached)? Is it a bad idea to try and drill them out? I do have compatible but more modern replacement plugs standing by. Thanks for any wisdom.

 

[Bama Rambler]

Since you suspect water under the shell I'd drill them out with a pneumatic drill. Or a very long bit extension and a cordless drill. I'd try to drill it pretty close to the size of the plug without getting into the threads. That way you can 'peel' the remaining piece out and clean up the threads.

 

[aharon]

Well I drilled through and found nothing at all underneath.
Now to extract the plug. Does this indicate there's low risk of the pool heaving?

 

[Richard320]

Well I drilled through and found nothing at all underneath.
Now to extract the plug. Does this indicate there's low risk of the pool heaving?

I think the pool would have lifted as soon as you emptied it if there was water underneath.
Like this And here what happen with and empty pool and lots of rain

 

[tamglud]

Hi aharon,

I hope you have had success with your project and that the pool hasn't lifted!! I have mine drained (I live in northern VA) since Wednesday and I'm having significant anxiety about the pool lifting. We are repainting and have been delayed because of incorrect primer which is why the pool has been empty. Fingers crossed for both of us!

THANK YOU for posting a picture of your plug (Custom 25523-900) because I've been looking online for that plug for DAYS without any luck until you posted a picture so that I could read the number! (We also have a Hayward SP1022B which we had to chisel out years ago and this time around - fortunately the hayward SP1022B is easier to chisel out because it's so shallow in comparison to the Custom one).

I was thinking of replacing the plugs Custom and Hayward with the new hydrostatic valves but have read so many poor reviews about them failing because of the O-ring? Undecided as of yet.

I'm wondering what you have found for replacements? I am seriously thinking of putting the exact same models back in.

Good luck!

 

[PoolGate]

This thread makes me happy i live on a hill. There would need to be 40 feet of rain for us to even get close to flooding.

 

[kadavis]

Anthony & Sylvan Josam Plastic "T" Wrench For Plug (#59010220)

Anthony & Sylvan Josam Plastic "T" Wrench For Plug (#59010220)

www.poolpartsunlimited.com

 

[aharon]

I was thinking of replacing the plugs Custom and Hayward with the new hydrostatic valves but have read so many poor reviews about them failing because of the O-ring? Undecided as of yet.
I'm wondering what you have found for replacements? I am seriously thinking of putting the exact same models back in.

I bought Hayward SP1056 valves thinking that the height would save me from the hassle of drilling plugs again someday, and quickly realized that A) that's probably not going to be a problem given that my water table appears to be too deep for any pressure to develop and B) for me, valves with O-rings are just introducing another point of failure and C) I'm probably just going to make things difficult for my poor robot.
So I'm thinking of going back to a low-profile plug of some kind, maybe your Hayward SP1022B if it is easier to remove. I have an old one with a simple wrenchable cube on the top which might be a good choice, similar to this: HAYWARD | PLUG ONLY WITH SQUARE HEAD, 1 1/2" MPT, WHITE | SPX1051Z1
In the meantime, given the apparent lack of urgency, I'm taking the time to powerwash the plaster. It's still a bit too cold to swim anyway in PA, unheated.

 

[tamglud]

Anthony & Sylvan Josam Plastic "T" Wrench For Plug (#59010220)

Anthony & Sylvan Josam Plastic "T" Wrench For Plug (#59010220)

www.poolpartsunlimited.com

Thanks for the picture...Instead of a T wrench, we used the sloted end of a pry bar to open the valve (Custom 25523-900) pictured above. We used the hooked handle at the top of the pry bar use a lever to turn, and to get extra leverage we hooked a hammer around the top of the hooked handle of the pry bar to loosen the valve. Worked perfectly!