Another problem! I'm trying to fire up a engine that was rebuilt 10 years ago. It has AFR heads that use studs instead of head bolts. A couple of the studs and nuts tear up with water and eventually drip. I read from a 28 year old book "How to Hotrod Small-Block Chevys" and if I read it correctly, it says when assembling use a non-hardning sealer on the threads. Is this just to keep the studs rust free or to keep water from leaking. I'm wondering if I should pull the heads and replace the head gaskets? Does anyone know the correct torque for Aluminum heads?