SBC drain plug

[DomSmith]

Ok I've searched previous posts w/o luck and need a quick question answered. Where is the engine block drain plug (for draining the cooling system) for a SBC? I don't have a service or Haynes manual for the motor. I'm replacing the radiator and will be draining and flushing the system. Thanks,
Dom

 

[Rice]

If I remember correctly there are several castings with bosses for the drains but they were not drilled. Simply hope yours are there.

If looking up at the engine from underneith you should find a plug on each side of the block (about mid block front to rear) just above the oil pan. If you run blockhugger headers getting them out ranks right up there with getting toothpaste back in the tube.

If your block does not have them (or you can't get to them) then you're left with simply draining the radiator and then pulling the bottom hose which still leaves quite a bit in the engine.

Good luck,
Rice

 

[Plowboy]

two other options if you can't get the 1/4 plugs out, are either knock out a freeze plug on each side of the block or what I normally do is pull a bottom head bolt and run a 3/8 inch tub down the hole and syphen the remaing water out.