I'm replacing the intake/exhaust manifold gasket on my 1989 cherokee limited with 4.0 6 cylinder. My question is whether I have to drain the cooling system or not. My shop manual says yes and my tech manual doesn't say to drain the system. I have looked at the new gasket and can see no open holes which would account for coolant circulating through the manifold or any exterior coolant hoses connected to the manifold.
I know it's not big job to drain the system but it is messy and wasteful if not necessary.
thank you