I am at my wits end. I cannot solve this overheat problem even with 3 manuals(including greenbooks) all of your advice out there and a friend who is a city mechanic.
Things I have done:
1. I have three working thermostats that open in boiling water. One is a 160, two are 180's. Neither type helped or hurt.
2. Replaced head gasket, twice, and changed the holes to match better the water holes.
3. Pulled the distribution tube and increase the slot size to the cylinders
4. New 4 lb rad cap.
5. Timed 10degrees, valve lash correct .020, idle 800rpms, carb rebuilt and set correctly
6. Fan mounted correctly
7. Radiator has 15degrees difference in in temp and out
8. Temp gauge reads correctly
9. New water pump
10. 50/50 coolant mix
So what am I missing? Engine has been cleaned and blown out and flushed.
The only thing I have left to suspect is the water pump. The old one was still working so I guess I will change them out. Yes it is hot here, 102 in the garage but it did not overheat before I had to pull the engine. I have pictures of the latest readings. It did boil over this time.