How do you service a Delta 1348 shower faucet?

Answer 1

SHUT OFF THE WATER.

After removing the knob and the chrome trim you need to remove the 'bonnet' ring before you can replace the cartridge or o-rings and springs. The tough part of this project is getting this bonnet ring off!! The bonnet ring is at the very front of the assembly, about 2" in diameter and 1/2" wide. You have to look carefully to see that this ring is not part of the valve assembly.

DON'T use a channel lock, pipe wrench or even a strap wrench on the bonnet ring. If you do you will either deform the ring and make it very difficult to remove or you will cause the whole valve assembly to turn shearing off some small tubing just behind the valve assembly. I could not get the bonnet ring off of my faucet easily. I started to use a wrench and when the whole assembly started to turn I stopped.

I found the applying some 3M 5-in-1 penetrating oil to the small gap between the bonnet ring and the valve assembly and waiting for about 10 minutes, I was easily able to spin the bonnet ring off by hand. I've seen posts elsewhere on the net that suggests using a rag soaked in warm vinegar over the ring, however I didn't try this myself.

I used Google to search for a good price on a replacement cartridge.