I have a setup where there are three handles, A hot and cold water and a diverter valve. When in shower mode, half the water comes out the spigot.
I replaced the diverter valve with an exact replacement (it's a Sayco) and I have the same problem. To get into shower mode you turn the diverter out (counterclockwise) so it can't be a problem with the seat, because that doesn't come into play here.
Anyone have an ideas ?
Thanks

 

There is a washer that is missing on that diverter stem and it is not the one at the end of the stem; it is the one that the stem backs up against to the front of the stem housing.

They are 19 cents and that will fix your problem 100%. It is made out of a hard black plastic with a large opening; the stem will have to be removed from the housing to install this washer, the old one deteriorated and fell off.

 

Wow! I had *exactly* the same problem you describe after replacing my Sayco 9B-5D diverter. I purchased the entire kit from Ace Hardware that included the diverter, hot and cold valves, knobs, etc. I figured that kit would come with everything necessary. I do remember after pulling the diverter out looking in the hole and seeing a chewed up O-ring and I pulled it out without giving it much thought. I put all the parts in that came in the kit and I had the problem you describe. I put the old diverter back in and still had the problem. I figured there was some sort of O-ring or gasket missing but I'll be darned if I could find any sort of parts breakdown showing how things should be. So after finding this thread I decided to stop by Home Depot last night. They had a Sayco 9B-5D diverter hanging on the wall and after looking it over I didn't see any difference between it and the one I installed. I then noticed the package had been opened so I grabbed another one off the wall that hadn't been opened. BINGO! I immediately knew what my problem was. There was an O-Ring on this one in a key place. My replacement kit didn't include this O-Ring nor did it mention needing one. Well, you need it. It's a #7 O-Ring and here's where it goes:



I believe the picture actually shows it (I drew the arrow and added the text). You can get the O-ring from Home Depot, or probably anywhere else as far as that goes. Good luck!

Void Main

 

i have a setup with a handle that controls water temp, with a knob on it to control water flow that has the same problem - when i pull the little thing up on the bath spout to switch over to shower, water still pours out.
here's what the underside of the pull looks like... not sure how to remove/fix it.

edit: i found this FAQ... will get creative (after i take a shower, just in case )