Bathtub Diverter Not Fully Diverting

[Guy_From_Georgia]

I have a 40 or 50 year old home. The (apparently original) bathroom has your basic cast iron tub with three knobs. The diverter has always leaked pretty badly, in that it doesn't divert all the water flow-- all the water stays in the tub, but the shower just doesn't see as much of the diverted flow as it should.

I have tried several times to replace the valve stem. I assume the ones I'm being sold are not quite the right ones, though I guess there could be some internal problem. Hot and Cold valves close with no leaks, and replacement valve stems for hot and cold work just fine.

The only valve stem I have to match up, therefore, seems to be slightly incorrect. Plumbers I have asked don't want to bother with this, though they'd be happy to rip out the tile and the wall to fix this up for a tidy sum. (Um, no thanks.)

Some newer tubs have only hot & cold valves, and a diverter spout (please forgive me if I'm using the wrong terms here) where you pull up a lever and and the tub spout shuts and sends the water flow up to the shower head.

Here is my question: What if I just leave the diverter knob set roughly in the middle and switch to a diverter tub spout to turn the shower on and off? Or is there a simple way to remove the valve stem and cap that off if need be? (I suspect such a "fix" would be ugly unless there is cosmetically reasonable part made for this which I have never seen.)

I'm concerned that the old valve stem set half-diverted might restrict shower flow... Apart from that, is there some danger in trying this which I might not be foreseeing?

What happens if the diverter spout is flipped while the diverter valve is "down" to the tub? Would it just turn off the water, or is that too much force and it could break the spout diverter? What if the diverter knob is set to the shower plus the diverter spout is set to divert to shower? That seems less likely to cause an issue, but Id like to know.... (I have a could of reasonably young kids, so I KNOW at some point they will decide to try what I tell them not to do....)

Got any other, simple suggestions? I need a cheap fix here. This is an old bathroom, the goal is functional and not absolutely absurd looking, but I'm dumping a LOT of water down the drain with showers right now-- that seems a terrible waste.

Thanks!

 

[journeyman]

you would be better off installing a new shower valve and that way you will not have anymore problems. and just out of curiosity did you replace the seats when the stems were replaced

 

[Guy_From_Georgia]

you would be better off installing a new shower valve and that way you will not have anymore problems. and just out of curiosity did you replace the seats when the stems were replaced

Absolutely— I replaced the seats as well. I remember well, because I didn't do it with the first try, because I couldn't find the right wrench here. My tools all seem to walk away... Assumed that was the cause, went back to the store for the wrench, replaced the seat and found no improvement.

Figured the stem might be wrong for the diverter valve somehow though it didn't make sense— it all looked like the same sizes as before. Went back to Home Depot and got a fresh set. No change.

Decided it must me some problem with the design of the parts. Tried a different brand from Lowes. No change. I cannot see how it could not work, but it obviously does not.

Replacing the valve is gonna be a challenging situation because of the tile wall, and this is the only tub in the house and one of only two showers. Without going into excessive details, one of the kids is not gonna deal with not using this particular bathroom while the wall gets torn apart and repaired, nor to I have a ton of time or money to do that. (If the water were leaking into the wall, that would be another matter.)

Clearly I’m no plumbing expert, but I cannot see a danger in adding a diverter to the spout. Am I wrong?

Isn’t all those diverter spouts usually do to divert the water up through a second attached pipe to a shower head? I had always just assumed that without a conventional diverter valve, gravity made water stay out of the shower unless the diverter spout blocked the lower exit. Is there more going on there?

If I’m right, then if the original diverter is set in the middle, the diverter spout would be doing the same thing, except the shower might have slightly reduced volume of flow, but then again, then this was built it was to carry a lot more water than now needed to the shower. This shower head is a modern low-flow, while the old tub faucet is carrying enough volume to charge a small fire hose.

Besides, the old diverter won’t fully divert to begin with, so that would mean even less pressure could build up on the spout’s diverter.

 

[journeyman]

the guy at home depot probably gave you price phister parts. there are hundreds of manufactures that copy each other. home depot is not a plumbing store. go to the professionals. if they cant find the part they will tell you to change valve. if there is drywall behind tub you can still buy a three handle price phister valve. that way you dont have to cut tiles