Take a look at the following photo:

The T-fitting has been installed at Ford's original location for the heater hose that is routed back to the heater core on the firewall. Obviously, this area on the engine is the place to tap into to get the hottest coolant possible before it would go back to heat the core that heats the cabin. Since I am running an electric cooling fan on my radiator, I decided to tap in here as well so that the thermostatic switch could turn the fan on and off. Before I installed the original heater hoses and plumbing, the switch would work fine and ground correctly to actuate the relay, etc, when the coolant rose to the appropriate temperature. Once I installed this T-fitting however, the switch will only ground when the lever on the dash is in the HOT position, sending coolant through the hose. 

It seems to me that if I want to tap into this location, I can either have one or the other, but not both. Does anyone have any recommendations? I would imagine that although it's tight, I can put a T back at the head location where the temp sender is located. I would rather not do that because of how tight it is back there to manifold and to the linkage, but I was wondering if there were any other options.

Daniel Jessup

Lancaster, California

aka "The Hot Rod Reverend"
check out the 1955 Ford Fairlane build at www.hotrodreverend.com