Replace Seat for 1 Piece Toilet

You would think replacing a cracked toilet seat is easy, but nooooo, not for a one piece toilet ! This is because there's no nut on the bottom side, so Kohler & others put anchors instead. Thru the years of water seepage, the two screws will be rusted stuck forever ....

Materials needed:
Penetrating oils like WD40, PB Blaster etc...
Big screw driver.
Vice grip
Small hack saw
#10 ribbed plastic anchor & screw for dry walls
Lots of patients

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Step 1: Remove the Toilet Screws

Flip the seat cap cover. If you're lucky enough that the screws turn loose, just remove the screws, put in a new hardware and you're done.

Step 2: Soak the Screws

Now, this is reality talking: most likely yours will be seized like mine .... So spray the area real good with penetrating oils (I used PB B'laster), over night if possible, and keep the exhaust fan on.

Step 3: Brute Force Time

After 2 days of soaking, mine still stuck. So I started cutting the plastic caps until I can pry the seat out.

Step 4: Remove the Screws

Once the seat is gone, you'll have enough room to cut the screws out. In my case, I griped the head and started gently rocking it back/fwd, all the while spraying. You're in good shape if little pieces of anchor metal starts coming apart. With a little luck and lots of patients, it'll pop out in one piece.

Step 5: All Ready for the New Seats

Cleanup you mess! The hardest part is done. Let the bathroom ventilate while you get the new toilet seat and hardware.

Step 6: Put in New Anchor & Seat

Instead of the $45 Kohler part, I got a pack of #10 drywall anchors for $2. Works just as well.



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    7 Discussions


    3 months ago

    We have 3 Kohler 1-piece Rialto toilets. I replaced the seats on all 3 of them. The first two took about 2 minutes each. Unscrew bolt, replace seat, re-screw bolt. But the 3rd toilet had bolts that would not budge. I bought an impact screwdriver from Amazon and went to work. Using a small sledge hammer the first bolt finally loosened after about 30 blows. What a workout! The second bolt was more stubborn and the groove (flathead) at the top was beginning to widen causing the flathead bit to slip. I used layers of heavy gauze and plastic waterproof tape to narrow the groove and finally got the thing to unscrew. What a pain!


    3 months ago

    A pair of vice grips made short work of those bolts. I had a few Ikea drywall anchors that dropped right in for replacement. Thanks!


    4 years ago on Introduction

    I found a different anchor at Home Depot, it is called a " Triple Grip #12 " by Cobra, part number 173S. They come in a two pack with screws. It fits a little bit tighter than the #14 ribbed anchor shown. Either one works.

    1 reply

    Reply 1 year ago

    A sawzall and the Triple Grip #12 made it a 10 minute job! Mahalo!!!!


    The anchors shown were too small and fell into the holes on my toilet. You man need to get bigger anchors.

    1 reply

    You need to put the seat washer on and start the screws into the anchors a couple turns if they are loose before inserting them into the holes in the toilet. That helps the ones shown stay put. I tried a slightly bigger one (a powergrip #12) but found that one is too large.


    4 years ago on Introduction

    Thank you thank you thank you! I had the same problem as you and had no idea on what to do until now!