Hayward 200 Sand Filter


New member
Jun 6, 2019
Terre Haute, IN
I have a new dome gasket coming for my Hayward 200S. The filter is leaking after a sand replacement and reusing the old gasket. I've already removed the dome twice trying to fix leak with old gasket.

My question is, has anyone supplemented the gasket before with a bead of silicone (think Permatex Blue) or caulk? I ask because the previous owner put the dome right up against an inconvenient spot which makes a couple of the bolts hard to reach, so I really don't want to have to crack it a 4th or 5th time in case the new gasket leaks.

Bama Rambler

Mod Squad
TFP Expert
Bronze Supporter
LifeTime Supporter
Jun 22, 2009
SouthWest Alabama
It's best to use lots of pool lube instead of sealant. Just keep in mind that if you use some sort of sealant it's going to be a bear to get apart next time.


TFP Expert
LifeTime Supporter
Jan 6, 2010
San Dimas, CA (LA County)
Only use sealant if you never ever want to take it apart again.

A glazier friend who installs a lot of shower doors once told me that the caulk he uses holds 280 lbs per linear inch. RTV is not that strong, but I've had to remove valve covers with hammer and chisel before because someone glued things together.

The thing seals by deforming and compressing the O-ring. So make it easy for it to deform and lube it good. Lube it all. Any two points that touch, lube. Maybe some threads are galled and that little extyra friction prevents you from getting a good seal?

But don't put any hardening sealant on there.