Question: Engine Coolant Drain Plug

[alden]

Hi, I recently purchased a 1972 Corvette Coupe with a 454 ci /365 hp engine. I would like to change the engine/radiator coolant. Unfortunately, I am not able to locate the drain plug(s). Can anyone help?
Thank you. Alden

 

[Hib Halverson]

There are three drain plugs and all three must be opened to fully drain the system.

One is on the radiator. If you're sitting in the driver seat, it's on the lower right side of the radiator facing you.

There are two others on the engine block, one per side, above the oil pan rail at about the center of the block.

 

[alden]

There are three drain plugs and all three must be opened to fully drain the system.

One is on the radiator. If you're sitting in the driver seat, it's on the lower right side of the radiator facing you.

There are two others on the engine block, one per side, above the oil pan rail at about the center of the block.

Hello Hib Halverson, Thanks for the info. I readily found the radiator drain plug. It appears to be a 1/8" pipe thread with a hex head (please confirm). When I unthread the plug, the coolant is going to flow onto the crossmember of the frame. Is there a good way to collect the coolant? OR pull the plug and QUICKLY thread in a 4" long 1/8" pipe nipple? Should this be a 1/8" "drain cock" instead of a plug? Please advise. Thanks in advance, Alden

 

[Hib Halverson]

Hello Hib Halverson, Thanks for the info. I readily found the radiator drain plug. It appears to be a 1/8" pipe thread with a hex head (please confirm).

Hard to confirm without seeing the car or a picture.

When I unthread the plug, the coolant is going to flow onto the crossmember of the frame. Is there a good way to collect the coolant? OR pull the plug and QUICKLY thread in a 4" long 1/8" pipe nipple?

wash the coolant away or drain it into a bucket. It won't hurt the metal.

Should this be a 1/8" "drain cock" instead of a plug? Please advise. Thanks in advance, Alden

Usually, there's a drain cock there. When you pull the pipe plug you can replace that with a drain cock.