BuildCraft version: 7.99.24.1
Forge version: 14.23.5.2838
Singleplayer or multiplayer: SP only (due to OptiFine)
Steps to reproduce:

1. Place any engine in the world
2. Open inventory or press ESC
3. You will see that hotbar items are highlighted. Moreover, if you quit to the menu, you will see that items are visible on "Stopping internal server" screen.

Additional information: OptiFine version is E3 (older ones are crashing)

Easy solution, just turn off fast rendering.
Steps:

1. Open Minecraft
2. Go to Options
3. Go to Video Settings
4. Go to Performance
5. Turn off Fast Rendering if it isn't