My house came with this old pump for sprinklers. Now that Im doing the pool Im teying to fix my sprinklers because they never come on.
I noticed that the pump is broken, including the thread. The pipe is not broken but the actual pump.
If that has threads into the pump then it's a nipple on there that the PVC adapter is threaded to. If it's part of the pump itself the metal rotted and its replacement time. Cut it out and see what it looks like