Differences between Automotive and marine Head Gaskets?

[Gazjen]

To rebuild my engine I brought a automotive gasket set with brass freeze plugs I have now rebuilt my engine using the head gaskets that came with the kit I have now thought better of it and thought I'd order some marine head gaskets after reading in the manual not to fit automotive head gaskets ( I know reading after I'd already fitted them)

They came today and they look identical to the ones I have already fitted and are still magnetic as were the automotive ones.

So any ideas what the differences are?

am I going to be wasting my time swapping them over?

The replacements are GLM ones

Thanks again

[seapuppy]

Gazjen,
my understanding is that the head gaskets for a marine engine with raw water for cooling requires a head gasket with bronze sealing rings...and rims..the gasket material is the same....
for engines that have antifreeze as the coolant medium...steel is ok....

hope this helps..

SP