Diverter Issue

[Honeybee]

Hi, I have two showers that both have leaking diverters although all of the stems were replaced in 2020 (supposedly). Both showers are the 3 handle type. I matched the units to a Danco 9 in the hardware store. My diverter doesn't fit in unless I screw it to a shorter position which makes my diverter stem at least a quarter inch shorter than my cold/hot water stems. That being said, the hot and cold water operate great when running through the tub nozzle (no leaks at the hot/cold handles). When the diverter allows water to the shower head, about half of the stream comes out of the tub nozzle and half through the shower head. I thought this was a washer issue, so I purchased a replacement -- perhaps the wrong size (#11) or wrong location for the washer? I appreciate any advice as I only know enough plumbing knowledge to be dangerous.

Attached photos show the diverter opening, diverter with worn washer, diverter with washers side by side, and diverter with new washer installed.

 

[Geofd]

If you know the brand buy brand name replacement parts those off brand parts often
Don't work

 

[Honeybee]

I feel like I matched the brand. Are you saying the washer size is wrong for this model of stem?

 

[Geofd]

If you know the brand name of the valve use those replacement parts, not danco, if you don't take a picture of the whole valve and show us, someone may know it or bring that diverter and a picture of the valve to a plumbing supply house the guys at the counter usually have seen alot

 

[Twowaxhack]

It’s a Sayco

I work on those all the time.

This stem is put together properly except the o ring I circled appears to be too large. The o ring that goes in this location is thin.

You must remove the old oring out of the valve from the old diverter stem. They have a habit of staying in the valve.