Need some fan/cooling troubleshooting help

Last night i finally got my 88 tc in road worthy shape, and took it for a drive. I rebuild the engine and now have a SC50 installed. Anyway, it seems as if the primary electric fan is not turning on soon enough. It cycles on and off but seems as if its getting too hot b4 it turns on. Because the engine is totally rebuilt i didnt want to chance anything so i unplugged the a/c compressor and "turned on the a/c" so essentially just kept the fan running. It was probably around 20-30* outside and i kept the fan running all the time, and it maintained a temp at the middle of the gauge (whatever temp that is) to me that seems like it should have been cool not middle of the gauge. I can try a regular thermometer in the rad to check temp vs. gauge but what temp should the engine be at? I replaced the temp sensor/sender that is in the block (not the intake). Could that be the wrong part from ford and cause the fans to turn on incorrectly? Any ideas to check the problem area? With a previous 87 tc i had a cooling issue (typical prob) and just wired the second fan to come on with the primary (relayed). However with this tc before the engine rebuild ive never had an issue with cooling (which actually surprised me) so i left it alone. It seems as if the "turn on" temp is not working correctly, how can i test this. Thanks.

The sensor in the block has nothing to do with the fans. The sensor that provides info to the EEC for controlling the fans (87 & 88) is the ECT that sits between the middle two fuel injectors on the lower intake. The ECT can be bad and not set a code. I can send you some info on testing one, drop me an email.

It cycles on and off but seems as if its getting too hot b4 it turns on.

If you got a stock range thermostate it isn't going to open until around 192-195*F

A new engine may run slightly hotter than normal until broken in

If the coolant system is full and working properly, there is no way it should overheat while driving in this kind of weather. Your gauge may be off, they are not known for accuracy. My suggestion would be to put an aftermarket gauge in anyhow.

While you had it apart, did you remove and clean out the coolan fitting on the lower intake? These are often partially to fully blocked and it coolant can't flow here, then the fan system is not going to turn on at the correct temps

Pete I just sent ya an email. The thermostat should be a stock replacement, do you know what the fan "turn on" temperature should be? I bought it from ford but I believe they messed up and sent me the two temp senders instead of the ECT and sender. So i looked at the old one and the new ones (2) and noticed the senders had numbers on them (forget now, can check the usused unreturned one), but i matched up the number of the old on and it matched ONE of the new ones. Is that number a part # or a temp rating or something (thought it was 3 digits)? So i would think the gauge should be correct but i can check if i know the acceptable max temp or fan turn on temperature. Does that temperature match the themostat open temperature? I would think the intake temp inlet/outlet is clean i cleaned EVERYTHING up, but i guess it could've got overlooked??? doubt it tho. Thanks, just don't want to overheat it.

"The 4 blade fan is suppose to come on around 200-210 and go off at 190. It should also come on whenever the A/C is turned on. It should also run briefly every time the engine is started. The 7 blade doesn't come on until 220 and goes off at 210. It also comes on when the A/C head pressure reaches 310 psi. They are controlled through the EEC by the ECT (engine coolant Temperature sensor which is on the lower intake inbetween #2 & 3 fuel injectors.

I sent you some info

The ECT is much larger than a gauge temp sender

Thanks Pete, ill check my email. Guess ill check to see if my temp sender is accurate (within reason). If my gauge is off, i could be fooling me that its running hot, but if not i guess its ECT related.