diff --git a/src/main/java/org/cryptomator/cryptofs/fh/ChunkCache.java b/src/main/java/org/cryptomator/cryptofs/fh/ChunkCache.java
index 9e8e2a20..ee5eb56f 100644
--- a/src/main/java/org/cryptomator/cryptofs/fh/ChunkCache.java
+++ b/src/main/java/org/cryptomator/cryptofs/fh/ChunkCache.java
@@ -86,9 +86,10 @@ public Chunk putChunk(long chunkIndex, ByteBuffer chunkData) throws IllegalArgum
 				if (chunk == null) {
 					chunk = new Chunk(chunkData, true, () -> releaseChunk(chunkIndex));
 				} else {
-					var dst = chunk.data().duplicate().clear();
+					var dst = chunk.data().clear();
 					Preconditions.checkArgument(chunkData.remaining() == dst.remaining());
-					dst.put(chunkData);
+					dst.put(chunkData) //
+							.flip();
 					chunk.dirty().set(true);
 				}
 				chunk.currentAccesses().incrementAndGet();
diff --git a/src/test/java/org/cryptomator/cryptofs/CryptoFileChannelWriteReadIntegrationTest.java b/src/test/java/org/cryptomator/cryptofs/CryptoFileChannelWriteReadIntegrationTest.java
index 02bda852..2bcbaf42 100644
--- a/src/test/java/org/cryptomator/cryptofs/CryptoFileChannelWriteReadIntegrationTest.java
+++ b/src/test/java/org/cryptomator/cryptofs/CryptoFileChannelWriteReadIntegrationTest.java
@@ -53,7 +53,6 @@
 import java.util.concurrent.Executors;
 import java.util.concurrent.TimeUnit;
 import java.util.concurrent.atomic.AtomicBoolean;
-import java.util.concurrent.atomic.AtomicInteger;
 import java.util.stream.IntStream;
 import java.util.stream.Stream;
 
@@ -175,6 +174,25 @@ public void afterEach() throws IOException {
 			Files.deleteIfExists(file);
 		}
 
+		//https://github.com/cryptomator/cryptofs/issues/173
+		@Test
+		@DisplayName("First incomplete, then completely filled chunks are stored completely")
+		public void testFullChunksAreSavedCompletely() throws IOException {
+			int halfAChunk = 16_384; //half of cleartext chunk size
+			try (var writer = FileChannel.open(file, CREATE, WRITE)) {
+				writer.write(ByteBuffer.allocate(3 * halfAChunk), 0); //fill chunk 0, half fill chunk 1
+				writer.write(ByteBuffer.allocate(5 * halfAChunk), 0); //fill chunks 0 and 1, half fill chunk 2
+			}
+
+			try (var reader = FileChannel.open(file, CREATE, READ)) {
+				Assertions.assertAll(() -> reader.read(ByteBuffer.allocate(2 * halfAChunk), 0), //read chunk 0
+						() -> reader.read(ByteBuffer.allocate(2 * halfAChunk), 2 * halfAChunk), //read chunk 1
+						() -> reader.read(ByteBuffer.allocate(halfAChunk), 4 * halfAChunk) //read chunk 2
+				);
+			}
+
+		}
+
 		@Test
 		public void testLockEmptyChannel() throws IOException {
 			try (FileChannel ch = FileChannel.open(file, CREATE, WRITE)) {