I'm about to install Aqualisa MD 110 BSM bath/shower mixer. The installation instructions can be found on Aqualisa website here and the specific step I'm querying is at the bottom of page 25.

The package contains two sets of rubber gaskets: a pair of thing black one that fit in corresponding slots at the bottom of the tap tails:

enter image description here

and a pair of wide white ones, looking more like rubber washers:

enter image description here

The instructions state:

Place the rubber deck washers onto the tap tails and offer the assembly into position onto the bath.

Yet the corresponding image isn't very clear.

So my question is: do these need to go above the bath on the tap tails or just below the bath above the plastic nuts that screw onto the tap tails.

Bonus question: when I tighten the plastic nut on the tap tail below the bath, do I hand-tighten it or use a wrench? I don't feel that hand-tightening would provide a good water seal, but using a wrench, I'm afraid I might overtighten and break it.

  • My take on it is that the black o-rings are used in Step 1 and the white washers are used in Step 2... I'm thinking they'd go on top between the flange on the tail and the porcelain of the bath. Especially if they're kind of "rubbery" material. If they're more like fiberboard/cardboard, I'd put them on the underside with the nuts.
    – gnicko
    Commented Jun 16, 2021 at 15:27
  • @GregNickoloff Thanks. I don't think it's the case though. There is another pair of small washer-type rubber gaskets that go between the tap and the deck mount adapters. I skipped that part, as it's fairly straight forward.
    – Aleks G
    Commented Jun 16, 2021 at 15:33
  • OK. Reading the instructions more closely, I think the white rubber ones go on the top side of the tails where they go into the mounting holes... "... rubber deck washers onto the tap tails and offer the assembly into position" Makes me think to put the washers on the threaded portion and then insert the threads into the holes. Tighten the nuts from below...
    – gnicko
    Commented Jun 16, 2021 at 15:36

1 Answer 1


Put the rubber washers on the tap tails and inset the tails into the mounting holes. The white washers will be between the flange on the tap tails and the porcelain. Tighten the nuts on the bottom to secure the tap. I'm not sure, but I think the image shows the white washer in place under the "flange".

Hand tighten plus a quarter turn.

where to put white rubber washers

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.