Kohler body tile system issue

[boniam]

Hi,

I have about 10 year old kohls body tile system "Kohler K-10857-4-CP" with 3 body tile. In last few months one of bottom one is not flowing much water and top one had most water and second one has some. Also, water was kind of coming around the tiles (leaking) from first 2. I tried to take the tile plate out to see and i didn't know set screw goes in so that stripped couple of screws. In any case, i was able to take all three out and attached are pictures. Also I have noticed with shower tile plate out that second and bottom drips water for some time. Now questions that I have and i will appreciate if anyone case help.

(1) what may be reason to have no or very little water coming from bottom tile? Could it be just water pressure issue? How to diagnose or fix that?
(2) After putting it all back now it seems water is leaking from second one (not a lot). How to diagnose or fix that?
(3) what may be the reason that second one (and may be third one) drips water after turning off. It seems unusual that first one is not doing it.

I am not sure what parts to order (tile valve or plastic plate or all assembly) but i guess it depends on what the issues are. Attached are pic. First pic is every thing assembled and you can see some water coming from body from first and second. Second one is open with valve exposed. Third one is open and just plate taken off.

I am new to plumbing so will help any help.

 

[Rossando]

I recommend calling kholer. I would start with the cartridge but you might have other issues with each body sprayer. If you can remove the nozzle and blow it out it seems like crud got in. Does it happen on both hot and cold settings? What kind of heating system do you have(thankless,boiler or tanked water heater)?

 

[boniam]

Thank you @Rossando . This happens with both hot and cold. I have tankless gas heater.

Now my most immediate issue is I am not able to remove fitting to get to the nozzle which has Screen. After taking cover i was trying to remove waterway and adapter of third to see if there is some dirt there. https://resources.kohler.com/webassets/kpna/catalog/pdf/en/1095094-2.pdf is the installation instruction and it seems there is only one screw holding waterway in Step 6. But after removing screw it is not moving at all even after pulling with plier.

Any one has any idea how to remove this?

 

[boniam]

I could remove it and clean but water pressure is still very low in bottom body spray. I was looking through the original construction photos and found this plumbing photo. Is the plumbing issue here as it seems water pressure won't be good in bottom. How to correct this?