Customer complained of spongy feel, brought back to shop.

Techs noted stripped threads and removed hose/caliper. As threads were gone for 8mm bolt, they valiantly tried to install the latest 9mm bolt used on 105/ultegra shifters but port cracked as they were tightening.

It’s a noted problem with Shimano hydro shifters of cracking during tightening.

Shifter works perfectly but hydro port is cracked. You may be handier than our techs so here you go!

Techs drilled a hole for a brake cable and that seemed to work on the bench.

Maybe an epoxy solution could seal the port.

No hood.

In addition to the Tiagra 4700 series 10 speed derailleurs, any of the 105-Ultegra-Dura Ace 11 speed derailleurs will work with this shifter as the cable pull is the same.