Chunks in my coolant

Your running green antifreeze which doesn't like something aluminum in your system after sitting . Switch to the orange antifreeze. Small blocks were noted for aluminum timing covers and water pumps eating away with use of green antifreeze without the additive. Whenever you use anything in a cooling system such as . Intake, thermostat housing, timing cover, water pump, or radiator, you should use the correct anti freeze or those parts will corrode.