patch 7.4.883
Problem:    Block-mode replace works characterwise instead of blockwise after
            column 147. (Issue #422)
Solution:   Set Visual mode. (Christian Brabandt)
diff --git a/src/normal.c b/src/normal.c
index 69b0dce..b994056 100644
--- a/src/normal.c
+++ b/src/normal.c
@@ -9596,7 +9596,7 @@
 	    || (!initial && oap->end.col < W_WIDTH(curwin)))
 	return;
 
-    oap->block_mode = VIsual_active;
+    oap->block_mode = TRUE;
 
 #ifdef FEAT_MBYTE
     /* prevent from moving onto a trail byte */