Originally Posted by Senior Chief
Thanks John! The fan was changed to a high output electric fan do you think that could be part of the problem? I have been running it for years with no problems until recently.
Jim, Are you saying that the engine did not used to run hot but now it does? If that is the case, something must have changed.
I run a '51 Merc engine that is pretty well built. It sits behind a stock '36 ford radiator which is not even pressurized. The only time this engine even thinks about getting hot is on the interstate when it is 90 deg or higher out. Under no circumstances does it run hot at idle or around town. As I said earlier, the timing needs to be right and it is imparative that the radiator is fully utilized. The factory shrouds or baffles need to be installed so the hot air can not recirculate through the radiator. I personally run a Cooling Components electric fan and shroud which assures air is being pulled through the entire radiator.
One other thing I do is run a small block Chevy distributor which has been machined and set up with the correct advance curve for the flathead. That way I don't have to deal with the totally inadequate ignition that the flatties were built with.
Are your problems occurring on the highway at speed or around town and idling?