diff --git a/consensus/clique/clique.go b/consensus/clique/clique.go
index b593d2117d..e9a48316fd 100644
--- a/consensus/clique/clique.go
+++ b/consensus/clique/clique.go
@@ -42,7 +42,6 @@ import (
 	"github.com/ethereum/go-ethereum/params"
 	"github.com/ethereum/go-ethereum/rlp"
 	"github.com/ethereum/go-ethereum/trie"
-	"golang.org/x/crypto/sha3"
 )
 
 const (
@@ -641,11 +640,9 @@ func (c *Clique) Close() error {
 }
 
 // SealHash returns the hash of a block prior to it being sealed.
-func SealHash(header *types.Header) (hash common.Hash) {
-	hasher := sha3.NewLegacyKeccak256()
-	encodeSigHeader(hasher, header)
-	hasher.(crypto.KeccakState).Read(hash[:])
-	return hash
+func SealHash(header *types.Header) common.Hash {
+	encoded := CliqueRLP(header)
+	return crypto.Keccak256Hash(encoded)
 }
 
 // CliqueRLP returns the rlp bytes which needs to be signed for the proof-of-authority