Removing large threaded ring on my jacuzzi/carver cartridge filter

kevreh

In The Industry
Jun 2, 2007
444
Annandale, VA
There’s a large high strength plastic ring that holds the top onto my cartridge filter, it screws on. Part 7 below. About 24” diameter. Once it’s on there for a while it’s hard to unscrew. There were 4 tabs on the bottom of the ring I would hit with a mallet, 3 have broken off. The ring has some indented circles on the top, looks like some kind of tool fits in them (spinner wrench?) Whats the right way to loosen the ring?

Reference diagram;

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