What glue & screw/bolt/nut to use to fix the bathtub drain overflow?

[hunterex]

I was cleaning the bath tub and I had unscrew a cap from the side of bath tub (where the hole is located) below:

[![Whole bath tub][1]][1]

The cap consists of 2 partsart A & B as below

[![part A & B for cap][2]][2]

When I removed part B, the part A is connected by a screw, which comes from the drain overflow system behind the bath tub wall.
Here are the layout diagrams (assuming the screw coming from behind of the bath tub wall):

[![top view of part a with screw and part b][3]][3]

Here is the top view of part A with screw (which comes from the overflow drain system behind the bath tub wall)

[![top view of part A with screw][4]][4]

Lastly, take note that the white part of the part A would be glued to the bath tub wall. Again the screw comes from the overflow drain system behind the bath tub wall.

[![back of the part A with screw][5]][5]

However, by accident, I had pushed the screw into the inner part of bath tub.

1) Would there be any problem if I left the screw inside the bath tub?
2) The part A is held on the bath tub wall by a glue. What glue should I use to stick the part A on the hole? This is how I stick part A on the bath tub:
https://i.stack.imgur.com/dYzvr.jpg

[![how to place part A to bath tub][6]][6]
3) What screw, nut, bolt or other tool to hold part B to part A?

[![how to put part B to A][7]][7]

Any suggestion is welcomed! Let me know if you need more photos! Thank you.

**EDITED**

Further investigation reveals that there is a bath tub drain system installed in this bath tub, as seen in the image below:

[![Bath tub drain installed][8]][8]

This is the best I could do to get bath tub drain system out to the wall of bath tub, while waiting for a solution from you all on which glue to buy.

[![enter image description here][9]][9]

So only question remains now:
How to join part A, part B to the bath tub drain system behind of the bath tub?
What glue should I use to hold the bath tub drain system to the bath tub wall?
Thank you.


[1]: https://i.stack.imgur.com/74Uwf.jpg
[2]: https://i.stack.imgur.com/Bxn2Q.jpg
[3]: https://i.stack.imgur.com/VLx6F.jpg
[4]: https://i.stack.imgur.com/QB7c9.jpg
[5]: https://i.stack.imgur.com/sKLO7.jpg
[6]: https://i.stack.imgur.com/dYzvr.jpg
[7]: https://i.stack.imgur.com/VvDUa.jpg
[8]: https://i.stack.imgur.com/mSqxB.jpg
[9]: https://i.stack.imgur.com/BFhFo.jpg

 

[lostinthelight]

You could need to get your hand in behind the overflow to push it against the bath to connect the parts together unless theres some place to hook it back ,is there an access or removable panel on the bath? Some cleaning regieme you have Btw

 

[hunterex]

There is no removable panel on the bath.... not as far as I have discovered or knew.. It is difficult to hold it actually

 

[lostinthelight]

That big chrome disc is the cosmetic cover for the overflow, I think the plastic nut should separate from it as that should holds the part thats fallen down together. there needs to be a watertight seal between that and the bath

 

[hunterex]

How do I make a watertight seal? Which part needs to be sealed together? Do you mean sealing this with the part inside the bathtub?

 

[terryplumb]

The part of the overflow that is on the " blind " side of the bath has a rubber seal ,visible in your pic. It is that seal that makes the fitting watertight to the bath. You must hold this fitting in place ,centred over the hole in the bath,whilst fitting parts " A" and "B" to it. You can put a bead of silicone on the white bit of part A if you wish ,then put it in position , then part B screws onto the threaded rod of the fitting that protrudes from the blind side of the bath.

 

[lostinthelight]

Not yours but this may give a better idea

 

[dal5band]

Maybe the screw you have is nothing to do with this fitting. Push the white centre of B into the centre of A, then screw that ontothe the bolt in the centre ofthe overflow pipe fitting. You definately have to hold the overflow from behind over the hole as Terry above says.

 

[dal5band]

Where did you get that screw from ?

 

[hunterex]

Where did you get that screw from ?

Hi thank you for the response. The screw is already part of the overflow drain system as seen in the image here:

Can I pull the screw out to the hole while I apply the silicone glue? Any silicone glue will do?

 

[terryplumb]

If you can't support the fitting from behind the bath ,you have next to no chance of getting it back together.

 

[Madrab]

You need to get the bath panel off, has the panel been tiled over? You won't be able to fix that without getting to the back of the bath.

You could just silicone a flat piece of plastic over the overflow in the short term to allow you to use the bath till it's fixed. Just don't fill the bath up too much.

 

[lostinthelight]

Hi thank you for the response. The screw is already part of the overflow drain system as seen in the image here:

Can I pull the screw out to the hole while I apply the silicone glue? Any silicone glue will do?

There seems to be some confusion going on here, well to me anyway.
In the picture you seem to be refering to the thread in the overflow part behind the bath as “the screw” yet there is previous pic of a thread with a head on which looks like a separate screw.
Can you confirm if they are one and the same thing or different parts.If different, is there an internal thread in the one with the head...can you post pics of that part from each end.

 

[hunterex]

There seems to be some confusion going on here, well to me anyway.
In the picture you seem to be refering to the thread in the overflow part behind the bath as “the screw” yet there is previous pic of a thread with a head on which looks like a separate screw.
Can you confirm if they are one and the same thing or different parts.If different, is there an internal thread in the one with the head...can you post pics of that part from each end.

Sorry for the confusion caused. I can confirm that there are the same one screw. I have edited the original post to reflect it.

 

[hunterex]

You need to get the bath panel off, has the panel been tiled over? You won't be able to fix that without getting to the back of the bath.

You could just silicone a flat piece of plastic over the overflow in the short term to allow you to use the bath till it's fixed. Just don't fill the bath up too much.

Ok there is a possibility to access the back of the bath tub. I need your advice below:
Here is the left part of the bath tub

Here is the right side of the bath tub

How do I open the panel? If it is open, how do I close it?