diff --git a/common/buildcraft/builders/BlockBlueprintLibrary.java b/common/buildcraft/builders/BlockBlueprintLibrary.java
index f06f4beb..cea6a6cf 100644
--- a/common/buildcraft/builders/BlockBlueprintLibrary.java
+++ b/common/buildcraft/builders/BlockBlueprintLibrary.java
@@ -43,12 +43,15 @@ public class BlockBlueprintLibrary extends BlockContainer {
 		if (entityplayer.isSneaking())
 			return false;
 
-		TileBlueprintLibrary tile = (TileBlueprintLibrary) world.getTileEntity(i, j, k);
+		TileEntity tile = world.getTileEntity(i, j, k);
+		if (tile instanceof TileBlueprintLibrary) {
+			TileBlueprintLibrary tileBlueprint = (TileBlueprintLibrary)tile;
+			if (!tileBlueprint.locked || entityplayer.getDisplayName().equals(tileBlueprint.owner))
+				if (!world.isRemote) {
+					entityplayer.openGui(BuildCraftBuilders.instance, GuiIds.BLUEPRINT_LIBRARY, world, i, j, k);
+				}
+		}
 
-		if (!tile.locked || entityplayer.getDisplayName().equals(tile.owner))
-			if (!world.isRemote) {
-				entityplayer.openGui(BuildCraftBuilders.instance, GuiIds.BLUEPRINT_LIBRARY, world, i, j, k);
-			}
 
 		return true;
 	}
@@ -72,8 +75,9 @@ public class BlockBlueprintLibrary extends BlockContainer {
 	@Override
 	public void onBlockPlacedBy(World world, int i, int j, int k, EntityLivingBase entityliving, ItemStack stack) {
 		if (!world.isRemote && entityliving instanceof EntityPlayer) {
-			TileBlueprintLibrary tile = (TileBlueprintLibrary) world.getTileEntity(i, j, k);
-			tile.owner = ((EntityPlayer) entityliving).getDisplayName();
+			TileEntity tile = world.getTileEntity(i, j, k);
+			if (tile instanceof TileBlueprintLibrary)
+				((TileBlueprintLibrary)tile).owner = ((EntityPlayer) entityliving).getDisplayName();
 		}
 	}
 
diff --git a/common/buildcraft/builders/BlockMarker.java b/common/buildcraft/builders/BlockMarker.java
index 7340f814..bcdc0bdd 100644
--- a/common/buildcraft/builders/BlockMarker.java
+++ b/common/buildcraft/builders/BlockMarker.java
@@ -90,7 +90,9 @@ public class BlockMarker extends BlockContainer {
 
 	@Override
 	public boolean onBlockActivated(World world, int i, int j, int k, EntityPlayer entityplayer, int par6, float par7, float par8, float par9) {
-		((TileMarker) world.getTileEntity(i, j, k)).tryConnection();
+		TileEntity tile = world.getTileEntity(i, j, k);
+		if (tile instanceof TileMarker)
+		((TileMarker) tile).tryConnection();
 		return true;
 	}
 
@@ -117,7 +119,9 @@ public class BlockMarker extends BlockContainer {
 
 	@Override
 	public void onNeighborBlockChange(World world, int x, int y, int z, Block block) {
-		((TileMarker) world.getTileEntity(x, y, z)).updateSignals();
+		TileEntity tile = world.getTileEntity(x, y, z);
+		if (tile instanceof TileMarker)
+		((TileMarker) tile).updateSignals();
 		dropTorchIfCantStay(world, x, y, z);
 	}
 
diff --git a/common/buildcraft/energy/BlockEngine.java b/common/buildcraft/energy/BlockEngine.java
index 740a6df9..c5db6446 100644
--- a/common/buildcraft/energy/BlockEngine.java
+++ b/common/buildcraft/energy/BlockEngine.java
@@ -95,7 +95,7 @@ public class BlockEngine extends BlockBuildCraft {
 	@Override
 	public boolean onBlockActivated(World world, int i, int j, int k, EntityPlayer player, int side, float par7, float par8, float par9) {
 
-		TileEngine tile = (TileEngine) world.getTileEntity(i, j, k);
+		TileEntity tile = world.getTileEntity(i, j, k);
 
 		// Drop through if the player is sneaking
 		if (player.isSneaking())
@@ -117,10 +117,13 @@ public class BlockEngine extends BlockBuildCraft {
 
 	@Override
 	public void onPostBlockPlaced(World world, int x, int y, int z, int par5) {
-		TileEngine tile = (TileEngine) world.getTileEntity(x, y, z);
-		tile.orientation = ForgeDirection.UP;
-		if (!tile.isOrientationValid())
-			tile.switchOrientation(true);
+		TileEntity tile = world.getTileEntity(x, y, z);
+		if (tile instanceof TileEngine) {
+			TileEngine engine = (TileEngine)tile;
+			engine.orientation = ForgeDirection.UP;
+			if (!engine.isOrientationValid())
+				engine.switchOrientation(true);
+		}
 	}
 
 	@Override
@@ -131,9 +134,9 @@ public class BlockEngine extends BlockBuildCraft {
 	@SuppressWarnings({"all"})
 	@Override
 	public void randomDisplayTick(World world, int i, int j, int k, Random random) {
-		TileEngine tile = (TileEngine) world.getTileEntity(i, j, k);
+		TileEntity tile = world.getTileEntity(i, j, k);
 
-		if (!tile.isBurning())
+		if (tile instanceof TileEngine && !((TileEngine) tile).isBurning())
 			return;
 
 		float f = (float) i + 0.5F;
@@ -158,10 +161,10 @@ public class BlockEngine extends BlockBuildCraft {
 
 	@Override
 	public void onNeighborBlockChange(World world, int x, int y, int z, Block block) {
-		TileEngine tile = (TileEngine) world.getTileEntity(x, y, z);
+		TileEntity tile = world.getTileEntity(x, y, z);
 
-		if (tile != null) {
-			tile.checkRedstonePower();
+		if (tile instanceof TileEngine) {
+			((TileEngine) tile).checkRedstonePower();
 		}
 	}
 
diff --git a/common/buildcraft/factory/BlockQuarry.java b/common/buildcraft/factory/BlockQuarry.java
index 520f7721..6419aec3 100644
--- a/common/buildcraft/factory/BlockQuarry.java
+++ b/common/buildcraft/factory/BlockQuarry.java
@@ -56,8 +56,9 @@ public class BlockQuarry extends BlockBuildCraft {
 
 		world.setBlockMetadataWithNotify(i, j, k, orientation.getOpposite().ordinal(), 1);
 		if (entityliving instanceof EntityPlayer) {
-			TileQuarry tq = (TileQuarry) world.getTileEntity(i, j, k);
-			tq.placedBy = (EntityPlayer) entityliving;
+			TileEntity tile = world.getTileEntity(i, j, k);
+			if (tile instanceof TileQuarry)
+				((TileQuarry) tile).placedBy = (EntityPlayer) entityliving;
 		}
 	}
 
diff --git a/common/buildcraft/factory/BlockTank.java b/common/buildcraft/factory/BlockTank.java
index 8d480746..a0abe6ea 100644
--- a/common/buildcraft/factory/BlockTank.java
+++ b/common/buildcraft/factory/BlockTank.java
@@ -92,44 +92,47 @@ public class BlockTank extends BlockContainer {
 		if (current != null) {
 			FluidStack liquid = FluidContainerRegistry.getFluidForFilledItem(current);
 
-			TileTank tank = (TileTank) world.getTileEntity(i, j, k);
+			TileEntity tile = world.getTileEntity(i, j, k);
+			if(tile instanceof TileTank)
+			{
+				TileTank tank = (TileTank)tile;
+				// Handle filled containers
+				if (liquid != null) {
+					int qty = tank.fill(ForgeDirection.UNKNOWN, liquid, true);
 
-			// Handle filled containers
-			if (liquid != null) {
-				int qty = tank.fill(ForgeDirection.UNKNOWN, liquid, true);
+					if (qty != 0 && !BuildCraftCore.debugMode && !entityplayer.capabilities.isCreativeMode) {
+						entityplayer.inventory.setInventorySlotContents(entityplayer.inventory.currentItem, InvUtils.consumeItem(current));
+					}
 
-				if (qty != 0 && !BuildCraftCore.debugMode && !entityplayer.capabilities.isCreativeMode) {
-					entityplayer.inventory.setInventorySlotContents(entityplayer.inventory.currentItem, InvUtils.consumeItem(current));
-				}
+					return true;
 
-				return true;
-
-				// Handle empty containers
-			} else {
-				FluidStack available = tank.getTankInfo(ForgeDirection.UNKNOWN)[0].fluid;
+					// Handle empty containers
+				} else {
+					FluidStack available = tank.getTankInfo(ForgeDirection.UNKNOWN)[0].fluid;
 				
-				if (available != null) {
-					ItemStack filled = FluidContainerRegistry.fillFluidContainer(available, current);
+					if (available != null) {
+						ItemStack filled = FluidContainerRegistry.fillFluidContainer(available, current);
 
-					liquid = FluidContainerRegistry.getFluidForFilledItem(filled);
+						liquid = FluidContainerRegistry.getFluidForFilledItem(filled);
 
-					if (liquid != null) {
-						if (!BuildCraftCore.debugMode && !entityplayer.capabilities.isCreativeMode) {
-							if (current.stackSize > 1) {
-								if (!entityplayer.inventory.addItemStackToInventory(filled))
-									return false;
-								else {
+						if (liquid != null) {
+							if (!BuildCraftCore.debugMode && !entityplayer.capabilities.isCreativeMode) {
+								if (current.stackSize > 1) {
+									if (!entityplayer.inventory.addItemStackToInventory(filled))
+										return false;
+									else {
+										entityplayer.inventory.setInventorySlotContents(entityplayer.inventory.currentItem, InvUtils.consumeItem(current));
+									}
+								} else {
 									entityplayer.inventory.setInventorySlotContents(entityplayer.inventory.currentItem, InvUtils.consumeItem(current));
+									entityplayer.inventory.setInventorySlotContents(entityplayer.inventory.currentItem, filled);
 								}
-							} else {
-								entityplayer.inventory.setInventorySlotContents(entityplayer.inventory.currentItem, InvUtils.consumeItem(current));
-								entityplayer.inventory.setInventorySlotContents(entityplayer.inventory.currentItem, filled);
 							}
+						
+							tank.drain(ForgeDirection.UNKNOWN, liquid.amount, true);
+						
+							return true;
 						}
-						
-						tank.drain(ForgeDirection.UNKNOWN, liquid.amount, true);
-						
-						return true;
 					}
 				}
 			}
diff --git a/common/buildcraft/transport/BlockGenericPipe.java b/common/buildcraft/transport/BlockGenericPipe.java
index 582e4230..b78508c5 100644
--- a/common/buildcraft/transport/BlockGenericPipe.java
+++ b/common/buildcraft/transport/BlockGenericPipe.java
@@ -1020,9 +1020,12 @@ public class BlockGenericPipe extends BlockBuildCraft {
 		boolean placed = world.setBlock(i, j, k, block, meta, 3);
 
 		if (placed) {
-			TileGenericPipe tile = (TileGenericPipe) world.getTileEntity(i, j, k);
-			tile.initialize(pipe);
-			tile.sendUpdateToClient();
+			TileEntity tile = world.getTileEntity(i, j, k);
+			if (tile instanceof TileGenericPipe) {
+				TileGenericPipe tilePipe = (TileGenericPipe) tile;
+				tilePipe.initialize(pipe);
+				tilePipe.sendUpdateToClient();
+			}
 		}
 
 		return placed;