Thats a good idea, thanks!

You can confirm that the spout is not the problem by removing the spout and running the bath water.

Op here. Just to make sure those who respond understand: the problem is that water comes from the shower when I turn the taps on, without pushing the diverter button. Like when I am trying to fill the tub, the water comes both from the spout and shower. When i am giving a bath to my toddler, I am getting drenched from the shower if I turn on the taps. And it was actually a licensed plumber who told me I need to replace the spout to resolve the problem. I think one of PPs was right that it has something to do with the pipe size, the volume of water when the taps are fully on exceeds what the spout/pipe can handle, and water shoots up in the shower. In which case, the new spout will not do anything.

The spout is cosmetic. It hides a pipe that comes out of the wall. Changing the spout doesn't change the function.

Anonymous wrote:OP here. I am watching videos on YouTube for past 2 days, googling the issue, and buying a longer and a shorter spouts, In case the size is the problem. I initially bought the same size as before but now wonder if it was the wrong size to begin with since the shower always leaked. I am closing my eyes and seeing tub spouts, gosh. I wish I would get a plumber but now it is too late, I put too much time into it. It's either me now, or the spout.

No, you're good. If the spout was the wrong length, you wouldn't be able to install it at all. Leaky spouts are due to either:
1. Leaky diverter valve (broken seal or cracked inner threads).
2. Hard water build-up.

Changing the spout should do it, but if you have really hard water, you could look into a whole house softener.

OP here. I am watching videos on YouTube for past 2 days, googling the issue, and buying a longer and a shorter spouts, In case the size is the problem. I initially bought the same size as before but now wonder if it was the wrong size to begin with since the shower always leaked. I am closing my eyes and seeing tub spouts, gosh. I wish I would get a plumber but now it is too late, I put too much time into it. It's either me now, or the spout.

It’s very tight. You need a specially grippy tool and plenty of strength.

The spout and the shower are connected together. Water will prefer to come out of the spout because it offers less resistance, when you close the diverter it's no longer the path of least resistance and water comes out of the shower instead. It sounds like your spout has just enough resistance that some of the water comes out of the shower. I know that this can be really annoying when you're trying to enjoy a soak.

You could put a shutoff valve on the shower head, like this:
https://www.amazon.com/shutoff-head%EF%BC%8CWater-Control-Pressure-Regulator/dp/B09V52H6BH/ref=sr_1_2_sspa

I think any other solution is going to expensive and may not work -- a bigger pipe from the valve to the spout, a different style of valve that actually shuts off the shower when you're using the tub, an in-wall diverter valve. All of those involve tearing the wall open.

I had a shower diverter issue which was 100% solved with replacing the tub spout (the kind with the diverter in it), so I think you have something else going on. You are probably on track with some kind of seal/washer, but you may be at the point where you don’t want to wind up with a very expensive problem. You might want to YouTube it to see what others do and see if there is one more simple fix before calling a pro.

How bad is the drip? Many shower heads behave this way. Did it just start?

Hi, I have just replaced my tub spout with a brand new one. The problem is, the water still diverts to shower when I turn the taps on full strength. That is, it leaks from the shower when the little knob on the spout is not in shower position. So, all this trouble of replacing it by myself, and still water drips on my head every time I turn it on. Has anyone else had this issue? Were you able to fix it by yourself? Also, after I removed a spout, I saw that there is a hole around the pipe that is only partially sealed with some rubber like substance, does anyone know what it can be? I need to put more of this stuff in there for better seal. Is it plumber's putty, or epoxy? Thanks.