Kohler AquaPiston Repair — Cracked Cap, Canister Gasket, and Fill Valve Replacement

In this video I walk through a repair on a Kohler toilet with an AquaPiston canister system. My brother-in-law told me this toilet was having an issue, so I took a look — and when I opened the tank, I found a cracked AquaPiston cap on top of the canister. The canister itself was still operating normally, but because the cap was cracked, it could shift out of place and affect where the refill water was directed after a flush. Since I already had everything apart, I also replaced the canister gasket, the fill valve, and upgraded the angle shut-off valve to a 1/4-turn style as preventative maintenance. In this video I cover: • What failed and how I found it • What likely caused the damage after recent plumbing work • Why I replaced the related parts while the tank was open • A simple tip to reduce stress on toilet internals during plumbing work I’ve listed the parts I used below in case you want to reference them. Parts Used: (As an Amazon Associate, I earn from qualifying purchases.) • Kohler AquaPiston Cap & Stem - GP1229656 https://amzn.to/4bPIQAu • AquaPiston Canister Gasket - GP1059291 https://amzn.to/4dmUYdi • Kohler Silent Fill Valve Kit - GP1083167 https://amzn.to/41fo6Mj • 1/4-Turn Angle Shut-Off Valve - BrassCraft G2CR19X (comparable to G2R17X C1) https://amzn.to/3O3kutQ ⏱️ Timestamps 00:00 Intro / Problem explained 00:48 What I found inside the tank 01:28 What likely caused the damage 01:53 Prevention tip during plumbing work 02:00 Replacing the cap & stem 02:29 Replacing the canister gasket 02:52 Replacing the fill valve 04:02 Upgrading the shut-off valve 05:24 Final thoughts & outcome If this video helped you out, feel free to subscribe — I post real-world DIY projects, repairs, and lessons learned from working on home improvement projects. Thanks for watching!