Is there a method for changing out an inline system Boiler pump?

Jonesey

Three years ago I replaced the motor, but not the flanges/body (black in picture below) on my Weil-McLain boiler. I'd like to replace the entire assembly but I don't know how to unweight the copper line going to the expansion tank (see red arrows)
. Is there a tool that'll slip in or something to unweight the flange and separate it from the system?
Thank you for any help!

hot_rod

Why do you want to replace the body?
A large screwdriver will separate the body, you will need to support the piping from above, somehow

Jonesey

So just support the piping and get a nice size flathead in there huh? That makes sense - thank you. I replaced the motor 3 years ago and it's loud upon startup but then calms down. Do you know if there's a better pump to put in? Perhaps a 007e type high efficiency? I'm not sure if that's appropriate for a system pump on a Weil McClain Boiler.

hot_rod

lets see more  of the piping. Where the expansion tank connects. The air purger type.
static fill pressure?

Jonesey

col
Cold pressure is ~12psi and hot ~15-17psi

HVACNUT

Is something wrong with the volute, or flanges? Leaking? If all is good, leave well enough alone. Kind of a tight spot. I would've done the same thing.