Installation:

Client – Windows Automatic Installation

Important note – this procedure works on a freshly updated Minecraft. For more complex installation, in particular with other mods, it may be preferable to use the manual procedure.

• 1. Download all the client BuildCraft packages that you want to install.
• 2. Download the Minecraft mod pack installation assistant
• 3. Download the latest BuildCraft mod pack description
• 4. Double click on the file mod_pack_installer.jar. If that doesn’t work, you probably need to install Java, from http://www.java.com/…nload/index.jsp
• 5. Select the pack that you want to install
• 6. You will now see all the files required. You may miss some BuildCraft packages, or some dependencies. Click on the “Download” button to get the files that are missing, and then “Refresh”.
• 7. Once everything is green, the “Install” button should be clickable. Click on it. Let it do the magic!

Client – Manual Installation

• 1. Starting BuildCraft, you will need to install Minecraft Forge
• 2. Get the client packages of BuildCraft that you want to use (see above). Here’s the dependency and content details:
  • Core: no dependencies, provides only basic functionalities.
  • Transport: Depends on Core, provides only pipes.
  • Factory: Depends on Core , provides automatic crafting table, mining well and quarry.
  • Builders: Depends on Core , provides land markers and filler.
  • Energy: Depends on Core , provides oil and engines.

1.6.41.6.2 buildcraft-A-1.6.2-4.1.2.jar

1.5.21.5.1 buildcraft-A-3.7.2.jar

Download Link: 

Minecraft 1.7.9