How to remove drop pipe from Grundfos SP

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I've pulled my 29 year old Grundfos 25S20 pump, it was on 1 1/4 galvanized pipe which is in need of replacement. The pump appears to have a 1 1/2 to 1 1/4 bushing screwed into it. This is the older style Grundfos, nothing solid to hang onto with a wrench. There is only about 1/4" or less sticking above the top piece of the pump. That cap looks like sheet metal which would be easily damaged by a wrench. If disassemble the top of the pump that piece cannot be removed out of the way because it will hit the hex on the bushing.

How does one get these things apart? What can I grab on the pump?

While I'm at it, the local well guys are suggesting using 1 1/2 sch 120 PVC pipe as a replacement. It is down 80'. Is this OK on a 2 hp 4" pump? Should I have a safety wire on the pump? Do I need a torque arrestor?


Cary Austin
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Lubbock, Texas
There should be some "flats" on the top bowl of the pump to hold with a pipe wrench. They aren't much, but should be there.

1 1/4" sch 80 is fine. Use a PVC 1 1/2X 1 1/4 bushing though.

Safety wire and torque arrestors are just things that become rigid or brittle and help stick the pump in the well. Just don't let the pump cycle on/off and there won't be any torque or worry about dropping.
Hey, wait a minute.

This is awkward, but...

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