diff --git a/core/coreapi/block.go b/core/coreapi/block.go
index 53d14dcc63a..561389f074f 100644
--- a/core/coreapi/block.go
+++ b/core/coreapi/block.go
@@ -12,6 +12,7 @@ import (
 	coreiface "github.com/ipfs/go-ipfs/core/coreapi/interface"
 	caopts "github.com/ipfs/go-ipfs/core/coreapi/interface/options"
 
+	mh "gx/ipfs/QmYeKnKpubCMRiq3PGZcTREErthbb5Q9cXsCoSkD9bjEBd/go-multihash"
 	blocks "gx/ipfs/QmYsEQydGrsxNZfAiskvQ76N2xE9hDQtSAkRSynwMiUK3c/go-block-format"
 	cid "gx/ipfs/QmeSrf6pzut73u6zLQkRFQ3ygt3k6XFT2kjdYP8Tnkwwyg/go-cid"
 )
@@ -44,7 +45,7 @@ func (api *BlockAPI) Put(ctx context.Context, src io.Reader, opts ...caopts.Bloc
 	if !ok {
 		return nil, fmt.Errorf("unrecognized format: %s", settings.Codec)
 	}
-	if settings.Codec == "v0" {
+	if settings.Codec == "v0" && settings.MhType == mh.SHA2_256 {
 		pref.Version = 0
 	}
 	pref.Codec = formatval
@@ -93,7 +94,11 @@ func (api *BlockAPI) Rm(ctx context.Context, p coreiface.Path, opts ...caopts.Bl
 	}
 
 	select {
-	case res := <-out:
+	case res, ok := <-out:
+		if !ok {
+			return nil
+		}
+
 		remBlock, ok := res.(*util.RemovedBlock)
 		if !ok {
 			return errors.New("got unexpected output from util.RmBlocks")
diff --git a/core/coreapi/block_test.go b/core/coreapi/block_test.go
new file mode 100644
index 00000000000..bef532fdc4a
--- /dev/null
+++ b/core/coreapi/block_test.go
@@ -0,0 +1,167 @@
+package coreapi_test
+
+import (
+	"context"
+	"io/ioutil"
+	"strings"
+	"testing"
+
+	mh "gx/ipfs/QmYeKnKpubCMRiq3PGZcTREErthbb5Q9cXsCoSkD9bjEBd/go-multihash"
+)
+
+func TestBlockPut(t *testing.T) {
+	ctx := context.Background()
+	_, api, err := makeAPI(ctx)
+	if err != nil {
+		t.Error(err)
+	}
+
+	res, err := api.Block().Put(ctx, strings.NewReader(`Hello`))
+	if err != nil {
+		t.Error(err)
+	}
+
+	if res.Cid().String() != "QmPyo15ynbVrSTVdJL9th7JysHaAbXt9dM9tXk1bMHbRtk" {
+		t.Errorf("got wrong cid: %s", res.Cid().String())
+	}
+}
+
+func TestBlockPutFormat(t *testing.T) {
+	ctx := context.Background()
+	_, api, err := makeAPI(ctx)
+	if err != nil {
+		t.Error(err)
+	}
+
+	res, err := api.Block().Put(ctx, strings.NewReader(`Hello`), api.Block().WithFormat("cbor"))
+	if err != nil {
+		t.Error(err)
+	}
+
+	if res.Cid().String() != "zdpuAn4amuLWo8Widi5v6VQpuo2dnpnwbVE3oB6qqs7mDSeoa" {
+		t.Errorf("got wrong cid: %s", res.Cid().String())
+	}
+}
+
+func TestBlockPutHash(t *testing.T) {
+	ctx := context.Background()
+	_, api, err := makeAPI(ctx)
+	if err != nil {
+		t.Error(err)
+	}
+
+	res, err := api.Block().Put(ctx, strings.NewReader(`Hello`), api.Block().WithHash(mh.KECCAK_512, -1))
+	if err != nil {
+		t.Error(err)
+	}
+
+	if res.Cid().String() != "zBurKB9YZkcDf6xa53WBE8CFX4ydVqAyf9KPXBFZt5stJzEstaS8Hukkhu4gwpMtc1xHNDbzP7sPtQKyWsP3C8fbhkmrZ" {
+		t.Errorf("got wrong cid: %s", res.Cid().String())
+	}
+}
+
+func TestBlockGet(t *testing.T) {
+	ctx := context.Background()
+	_, api, err := makeAPI(ctx)
+	if err != nil {
+		t.Error(err)
+	}
+
+	res, err := api.Block().Put(ctx, strings.NewReader(`Hello`), api.Block().WithHash(mh.KECCAK_512, -1))
+	if err != nil {
+		t.Error(err)
+	}
+
+	r, err := api.Block().Get(ctx, res)
+	if err != nil {
+		t.Error(err)
+	}
+
+	d, err := ioutil.ReadAll(r)
+	if err != nil {
+		t.Error(err)
+	}
+
+	if string(d) != "Hello" {
+		t.Error("didn't get correct data back")
+	}
+}
+
+func TestBlockRm(t *testing.T) {
+	ctx := context.Background()
+	_, api, err := makeAPI(ctx)
+	if err != nil {
+		t.Error(err)
+	}
+
+	res, err := api.Block().Put(ctx, strings.NewReader(`Hello`))
+	if err != nil {
+		t.Error(err)
+	}
+
+	r, err := api.Block().Get(ctx, res)
+	if err != nil {
+		t.Error(err)
+	}
+
+	d, err := ioutil.ReadAll(r)
+	if err != nil {
+		t.Error(err)
+	}
+
+	if string(d) != "Hello" {
+		t.Error("didn't get correct data back")
+	}
+
+	err = api.Block().Rm(ctx, res)
+	if err != nil {
+		t.Error(err)
+	}
+
+	_, err = api.Block().Get(ctx, res)
+	if err == nil {
+		t.Error("expected err to exist")
+	}
+	if err.Error() != "blockservice: key not found" {
+		t.Errorf("unexpected error; %s", err.Error())
+	}
+
+	err = api.Block().Rm(ctx, res)
+	if err == nil {
+		t.Error("expected err to exist")
+	}
+	if err.Error() != "blockstore: block not found" {
+		t.Errorf("unexpected error; %s", err.Error())
+	}
+
+	err = api.Block().Rm(ctx, res, api.Block().WithForce(true))
+	if err != nil {
+		t.Error(err)
+	}
+}
+
+func TestBlockStat(t *testing.T) {
+	ctx := context.Background()
+	_, api, err := makeAPI(ctx)
+	if err != nil {
+		t.Error(err)
+	}
+
+	res, err := api.Block().Put(ctx, strings.NewReader(`Hello`))
+	if err != nil {
+		t.Error(err)
+	}
+
+	stat, err := api.Block().Stat(ctx, res)
+	if err != nil {
+		t.Error(err)
+	}
+
+	if stat.Path().String() != res.String() {
+		t.Error("paths don't match")
+	}
+
+	if stat.Size() != len("Hello") {
+		t.Error("length doesn't match")
+	}
+}