Almost directly below the temp sender unit.

If it's a 51 to 54 block, the drain is above the starter and cover the starter before you remove the drain plug. If it's a 55 or 56 block, the drain is just back of the distributor, as they had to raise the starter to get engine into the Nash body.

Not a very good pic, but you can also put a petcock in there and make it a snap to drain it directly into a container (with a rubber hose).

Thanks for all the help. The picture was especially helpful. Unfortunately I now remember why I haven't drained the block for a while. The drain plug is frozen up solid. I wasn't in the mood to go through the agony of trying to get it out. Instead I took the lazy man's way. and just opened up the radiator hoses and ran the garden hose through the radiator and into the block at the top. It probably wasn't the best job but the water looked pretty clean when I stopped running the hose.

Once again, thanks for the help. You guys always come through.

Ed

remember Kroil, the best there is.

You really need to remove the plug to flush the block or overheating will plague you. I would try the kroil first, if not successful use heat but try to remove it. then put the hose in the t stat hole and while running water, use a small 1/8 in. drill bit and ream the hole until the water comes out clean. It will stop many times until you get all the rust and sludge out but necessary. Keep poking it until it runs clear for a few minutes. then stop the hose and let it drain out. Install a short nipple like 1-3 inches and then add a cap. this will make future cleaning a breeze. If you really want to clean the system, use a good flush first then a few table spoons of Iron Out from the grocery store, used for laundry and water softeners. this needs to be circulated for 1/2 hour and then set over night and flushed. All your rust problems will be gone after that kind of flush. It is sodium hydrosulfite on the 1 lb. bottle label, and is in most stores or Menards type supply places. Be sure to flush good after using this chemical. It is hard on hoses if left in the system.

Robert
Good tech information. Thank you. I have a question. What hole are you talking about reaming with 1/8th inch drill while flushing through the thermostat housing?

I might add to your tech tip: to use garden hose to flush and back flush the heater core as well until the water comes out clean. I guess mine hadn't been flushed for many years or ever.. I was surprised at how much crude had collected inside. It took many flushes before clean water began to come out. It took longer to clean the heater core than it did to clean the engine. I suppose the engine had been flushed before and the heater core had been neglected.
Lee O'Dell

Did you back flush the heater core? I believe the drill bit is to make sure no big particles are blocking the hole. I've had sediment in a boat motor that blocked the outlet. keep the water running while you work the bit in the drain.