1520 cc motor 1518 cc water jacket

[coastlinetrees]

putting on this jacket should i use both of the o rings that came with the ose jacket or are the other two just spares if it ever leaks fits nice just dont know if i need them both on the motor

[carlcisneros]

they are supposed to be spares according to the manufacturer of the jacket.
thats what they told me.

I got the same set up at home for my 2 1520's.