Well, now I've learned (the hard way) about the oil-filled fan hub assembly on the Flathead. Take it from me, if they don't have oil in them it will powder the impeller, shaft and everything else inside the hub.
Can anyone recommend a source for a NOS or reman hub assembly. Mine appears too far gone to save.
Be careful with the hub you get from C&G. I got one from them and the 8 bolts that hold the fan on were too short. I had to get new ones and they were hard to find.
I had to buy 8ea. 12-28 X 1 1/4" machine screws.
C&G had the screws in it to keep the thing together but they were not long enough to go through the fan too.
Other than this one event I am very happy with C&G.
I questioned same part # discepancy and it was explained to me that the 8603 number was the hub/pulley only which is indeed shown as obsolete by most all sources I found.
I was told the 8604 number was for the complete assembly (which I'm sure is a reproduction and not an NOS).
Regardless, for my purposes anyway, if it fits and works I'll be satisfied. If it doesn't I'll keep your info in mind. Thanks for the tip.