diff --git a/electrum/lnwatcher.py b/electrum/lnwatcher.py
index d3f831906..2a1fd16df 100644
--- a/electrum/lnwatcher.py
+++ b/electrum/lnwatcher.py
@@ -77,11 +77,10 @@ class SweepStore(SqlDB):
         return set([r[0] for r in c.fetchall()])
 
     @sql
-    def add_sweep_tx(self, funding_outpoint, ctn, prevout, tx: Transaction):
+    def add_sweep_tx(self, funding_outpoint, ctn, prevout, raw_tx):
         c = self.conn.cursor()
-        assert tx.is_complete()
-        raw_tx = bfh(tx.serialize())
-        c.execute("""INSERT INTO sweep_txs (funding_outpoint, ctn, prevout, tx) VALUES (?,?,?,?)""", (funding_outpoint, ctn, prevout, raw_tx))
+        assert Transaction(raw_tx).is_complete()
+        c.execute("""INSERT INTO sweep_txs (funding_outpoint, ctn, prevout, tx) VALUES (?,?,?,?)""", (funding_outpoint, ctn, prevout, bfh(raw_tx)))
         self.conn.commit()
 
     @sql
@@ -298,11 +297,6 @@ class WatchTower(LNWatcher):
             return await self.sweepstore.get_num_tx(outpoint)
         return self.network.run_from_another_thread(f())
 
-    def add_sweep_tx(self, funding_outpoint: str, ctn:int, prevout: str, tx: str):
-        async def f():
-            return await self.sweepstore.add_sweep_tx(funding_outpoint, ctn, prevout, tx)
-        return self.network.run_from_another_thread(f())
-
     def list_sweep_tx(self):
         async def f():
             return await self.sweepstore.list_sweep_tx()
diff --git a/electrum/network.py b/electrum/network.py
index 12876b12f..35a620c52 100644
--- a/electrum/network.py
+++ b/electrum/network.py
@@ -311,21 +311,21 @@ class Network(Logger):
         self.channel_db = None  # type: Optional[ChannelDB]
         self.lngossip = None  # type: Optional[LNGossip]
         self.local_watchtower = None  # type: Optional[WatchTower]
+        if self.config.get('run_watchtower', False):
+            from . import lnwatcher
+            self.local_watchtower = lnwatcher.WatchTower(self)
+            self.local_watchtower.start_network(self)
+            asyncio.ensure_future(self.local_watchtower.start_watching())
 
     def maybe_init_lightning(self):
         if self.channel_db is None:
-            from . import lnwatcher
             from . import lnworker
             from . import lnrouter
             from . import channel_db
             self.channel_db = channel_db.ChannelDB(self)
             self.path_finder = lnrouter.LNPathFinder(self.channel_db)
             self.lngossip = lnworker.LNGossip(self)
-            self.local_watchtower = lnwatcher.WatchTower(self) if self.config.get('local_watchtower', False) else None
             self.lngossip.start_network(self)
-            if self.local_watchtower:
-                self.local_watchtower.start_network(self)
-                asyncio.ensure_future(self.local_watchtower.start_watching)
 
     def run_from_another_thread(self, coro, *, timeout=None):
         assert self._loop_thread != threading.current_thread(), 'must not be called from network thread'