I Have created a monster grinder in a singleplayer creative world that's superflat with dispensers which are supposed to fire water to push monsters over a ledge. The dispensor is triggered with a redstone current for 5 seconds, then unpowered for 5 seconds, and being repeated. This is supposed to toggle the water on/off, but that never happens.
To resolve this issue temporarily, I have to break a block next to the dispensor when its triggered by the redstone but doesnt activate, then replace that block. It then pours the water. After this the same problem occurs over and over.
Some of the dispensors however do work, shown in the .pngs.
A similar issue I found is here, issue 105150
Environment
I'm using a laptop with Windows 10, Intel i3-7100U (2.4 GHz, 3MB Cache), Intel HD Graphics 620 (up to 2100 MB Dynamic Video Memory), 4 GB DDR4 Memory, 1000 GB HDD. Is not overclocked.
I type this into cmd for java version:
java --version
java 10.0.1 2018-04-17
Java(TM) SE Runtime Environment 18.3 (build 10.0.1+10)
Java HotSpot(TM) 64-Bit Server VM 18.3 (build 10.0.1+10, mixed mode)
Your dispensers are affected by quasi-connectivity, which is an Intended behavior: MC-108
You can fix your contraption by deactivating the layers from top to bottom. If you need more information about this stuff, check online about quasi-connectivity.