Antifreeze in the crank case, 196, help

[grendel_cave]

I was wondering if anyone might have any explanations (other than cracked head, block, or untrue mating surfaces) as to why I'm getting coolant in my engine oil. I recently rebuilt the 196, the block was decked, the head was milled (very reputable shop did the work), fresh head gasket. As far as I know all the head bolts are torqued to spec. Can coolant get into an IH engine, 196, if the manifold is not torqued to spec? I'm aware of the traditional reasons for coolant in the oil, but is there anything else particular to 196s that might cause a problem if not properly attended to? Any recommendations would be greatly appreciated.

 

[1975IH200]

A couple of sources come to mind:

1. A heater hose connected to a vacuum port of the intake manifold allows coolant from the heater in. Heater hose attached to the power brake vacuum hose fitting for example.

2. Utilizing an incorrect cylinder head gasket, ie. Ic gasket on a non-ic engine or non-ic gasket on an ic engine.

3. Similar to #2 above, only a bit different: ic head on a non-ic engine or non-ic head on an ic engine.

4. Improperly sealed/installed intake manifold & gasket.