Replacing A Toilet Fill Valve

 I wrote a post on clearing debris from a toilet tank's fill valve. The toilet in question worked well for about 2 months before relapsing. This time, I decided to replace the fill valve. I chose the following product from FluidMaster

https://www.amazon.com/Fluidmaster-Toilet-Fill-Valve/dp/B07N7BH94Q

The 400H Performax is an inexpensive option at around $14. It had good reviews and also allowed bowl water adjustment. It is also sold in a contractor version with a brass threaded pipe instead of PVC.

Removing the Fill Valve

I used the shutoff valve to turn off the water in the tank.

Flushing the tank did not eliminate all the water in the tank, and I had to use a plastic water bottle and sponge to empty the remainder.

I then disconnected the tube from the shutoff valve into the tank. This didn't require any special tools and could be loosened by hand.

The next step was the hardest - removing the locknut that attached the old fill valve to the tank. It was really tight, and it could not be loosened by hand. I ended up needing a vise grip.

The limited space around the toilet made this slow going with the vise grip. Additionally, the lock nut is deliberately designed for hand use. It was, therefore, very tricky for the vise grip to grab on tightly to the lock nut.

After about 10 minutes of struggling, I paused to think - and decided to push down on the valve with one hand. Pushing down on the value would squeeze the rubber gasket, reduce tension, and allow the lock nut to be loosened by hand.

Installing the new Fill Valve

The new Valve height had to be adjusted so that the top of the valve was roughly 3 inches higher than the intake. Since the intake was 5 inches below the top of the tank, the fill valve had to be 2 inches below the top of the tank.

I ensured that the new rubber gasket made a good seal with the hole, used the new lock nut, and tightened it by hand. The instructions recommend against over-tightening, but I wish there was a definitive way to know if this was over-tightened, given that different people have different arm strengths.

I did have to adjust the bowl water level by turning the bowl level knob to the middle. According to the instructions, the fill valve ships with bowl levels set to the correct levels. However, I had to adjust it because the bowl seemed higher than usual.

And that was it. Overall, this was an easy install except for the old locknut removal.