anyone have a 470

[spareparts]

on an 89 engine, the coolant reservoir should be part of the exhaust riser, the exhaust manifold should be made out of aluminum, while the exhaust riser/reservoir is cast iron. There were some early issues with the gasket leaking into #4 cylinder. It would be prudent to pull the spark plugs and do a compression test on the engine. Also look at the heat exchanger, it should be 4" in diameter, earlier ones were 3". Take a good look at the charging system, its built into the engine balancer, look at the windings behind the balancer to see if you can spot any corrosion. While you have your head down there, look for signs of antifreeze leaking from a small hole right at the base of the front timing cover, its a weep hole to allow coolant that has gone past the cam seals to leak out.