Flyfisherman128 wrote:
The timing is good, the plugs look good, compression is good. The fan blade is not the issue, it heats up before the fan ever kicks in.
If it heats up before the fan kicks in, there are two possibilities:
Thermostat and fan clutch that does not engage at the proper temperature.
Thermostats are cheap and easy to replace. Start there, though the fan clutch is high on the list.
Said another way, if the fan does not come on before overheating temperature is reached it is bad (assuming that you have used an IR gun to confirm that it is, indeed overheating).