Coolant selant in Aluminum engines
 

Has anyone heard of gm part 364621 it is an engine coolant sealer. Does any one know if there is an aftermarket product that does the same think. I have closed cooling on my boat and I have aluminum parts. Should I use this in my boat.

My cadillac has an aluminum motor and gm requires 1825-m coolant with this special 364621 sealant. I wonder if I should use the same stuff to protect the aluminum engine parts on my boat. the boat has closed cooling?

Is this snake oil or something special or new for aluminum engine parts?

I am glad someone went to gm school!

Thanks