Screenshots here:
https://drive.google.com/folderview?id=0BwHDCyyzhWpiNS1QVGYzeWhYMUU&usp=sharing
List:

• ItemBlockEnergyCube.java
• ItemFreeRunners.java
• ItemBlockGenerator.java
• ItemPartTransmitter.java Note: all names expect mod names should be split into .lang file
• ItemBlockGasTank.java
• ItemWalkieTalkie.java
• ItemAtomicDisassembler.java
• ItemScubaTank.java
• ItemJetpack.java
• ItemRobit.java
• ItemMekanismSword.java
• ItemMekanismTool.java
• ItemMekanismArmor.java
• ItemMekanismHoe.java
• ItemElectricBow.java (ON, OFF)
• GuiGasTank.java
• ItemBlockCardboardBox.java

Also, don't close it(until everything can be translated). For example when you added "Stored Energy: " line to .lang file(from ItemBlockMachine.java) you missed "Stored Energy: " from ItemBlockEnergyCube.java. So, ItemBlockEnergyCube.java can't be translated.
Here a lot of identical strings but they in different .java files. So, here a lot of work.

P.S I'll try to do a list of .java files.
P.S2 most things added but not all, I think.

Thanks so much for the list. About halfway done now.

EDIT: What needs to be done in the tool classes?
EDIT2: All done, except for the tool classes. Closing, let me know about the tool classes whenever.

In tool classes here "HP" "word" 😄 this can be translated too. Also, in ItemPartTransmitter.java lines 109-111 can be translated too. I am talking about: "RF ", "EU ", "MJ " mods names should stay in class file.

Found some more:

• MekanismKeyHandler.java
• MekanismRecipeHandler.java ("Shaped Mekanism Crafting")
• ItemConfigurator.java (" Set link to block ")
• MekanismUtils.java (" Using outdated version on one or more modules.", " Consider updating to version ", " New features: ", " Visit ", " to download.", "Using developer build ")

From first list:

• GuiGasTank.java ("Gas: ", "None", "Dumping...")