I Just bought a Mercury Villager 1995 with a 3.0 engine that was overheated and blew the head gaskets and did not start. The car looked very clean so I bought it and reworked the heads.

After start up the engine didnt have power.

I jacked the front and ran it. it went fast to about 3000 rpms. after 3 minutes run, I heard a thud and the engine went to normal speed and normal power. but it wont go on reverse. Park is OK. "R" goes forward, neutral goes forward, "D" goes forward, 2d goes forward. 1st it locks. Still It will not go on reverse.

Please advice

Please advice