Coolant leak and slow speed fan not working

[Lovel]

Have you ever tried nipping up both of the alloy manifold to cylinder head set pins? The card gasket joint does lose clamping force over time. There is a coolant gallery at each end that could leak into the cylinder and not show up in the vee. Failing that remove the manifold and fit new gaskets, remember to tighten the set pins again as with heat the manifold joint will loosen.