Yes, both caps are approximately 2 3/8″ inside thread diameter. They are NOT interchangeable. Look closely at the threads. 602-5321(middle photo) has a rounded thread. This is the current style. The older cap(bottom) 602-5301 has a much sharper angled thread. The change occurred in about 2010. If you can not remember what shape the old drain cap was round or hexagon you will need to examine the threads on the sand tank. Both caps require the same o ring (805-0224). All these parts are available at http://www.waterwayparts.com
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We just aquired a house with an above ground pool that has this style pump/filter on it. I have tried to put the drain cap on and it will not go on it does not want to thread correctly. Any ideas/suggestions? It is the new style cap.
https://wordpress.com/post/waterwayparts.wordpress.com/1676
Yes, both caps are approximately 2 3/8″ inside thread diameter. They are NOT interchangeable. Look closely at the threads. 602-5321(middle photo) has a rounded thread. This is the current style. The older cap(bottom) 602-5301 has a much sharper angled thread. The change occurred in about 2010. If you can not remember what shape the old drain cap was round or hexagon you will need to examine the threads on the sand tank. Both caps require the same o ring (805-0224). All these parts are available at http://www.waterwayparts.com