I contacted hayward directly and gave them the model number for my pump which is the SP 1593. My 1.5HP is fine for the filter I have surprisingly. They even recommended another type of filter, the S180T which is 150# like the one I have. Mine is just a different brand.
Thought I would just give you that input since it was someone directly from the manufacturer.
Thanks and I'll let you know if it is the multi valve gasket.
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