1966 mustang with a 302 rebuilt engine overheating-radiator changed with a 6 bladed fan-no improvement-needle is almost to the right side of the gauge-anyone have a similar problem with a correction-thanks

 

How's the thermostat? Do you notice any coolant disappearing / burning up but no external leaks ?

 

What kind of shape is the radiator in? Is the water pump pumping?

 

Those cars are pretty simple.

Either thermostat sticking or radiator is partially plugged up. Lot of those radiator tubes start getting slowly plugged up.

 

First check the temp sensor. If it is good, check the timing. running retarded will heat it up.

 

the car has a new radiator-temp gage-radiator 3 core-engine has been flushed out-engine has been rebuilt but when outside temp moves towards 90 degrees the temp gage moves to the right and using a digital temp gage-the reading is 230 to 240.

 

Check your timing as bop11 mentioned. You generally want to set your base timing as far advanced as you can get it (up to the point of pinging at idle), then drop it back about two or three degrees. Are you running an old school stock timing setup or do you have an aftermarket electronic setup?

If you're stock you may need to set your timing twice a year (winter/summer) if you're electronic, a lot of those just need the timing set once and then forget it since they have the ability to add/pull timing to a greater degree than the mechanical stock setup.

When did the problem start? right off the bat or been a while where it was running fine and just started having problems?


Here's a couple other ideas

Cooling fan clutch: is it thermostatic or solid? If it's slipping it won't cool down the car efficiently and would allow it to heat up, it will be more noticeable as the temps rise.

Water Pump: Do you have the correct water pump on there? Clockwise is the norm but you can accidentally install a counterclockwise and not know it until you have issues. They look and install identically but the impeller is "backwards" on the counter clockwise one.

 

Actually your temperature sounds about right. With 50% antifreeze and 5 psi cap you could be around 240°F and still be OK. Also check that you have the spring inside the hose from the bottom of the radiator to the block. Many people forget this but it is there to keep the hose from collapsing when it is hot and the pump is pulling hard. This spring was standard in the original but will get lost, or not even noticed when hoses or radiators are changed. It is very important! A collapsed hose will reduce coolant flow to almost nothing.

 

Okay...while 5 psi might allow temps to reach 240 before it pops the cap...I dont think anyone will recommend running an early v8 to that temp. There is debate about what is "too hot" if we were to plot what would be considered "safe temps" base on user input on this forum im sure it would follow a typical bell curve pattern...240 would fall at least 4 standard deviations away from the mean.

I would think 240 would result in engine damage over time if not directly. 220 should be your upper limit anything between 190 and 215 should prove to be quite acceptable.

-Gun

 

thanks for the info but the problem has been solved but 2 different repair shops will not admit to error on their part by not accessing the problem correctly and costing me more money-the problem was that the new 6 bladed fan was reinstalled incorrectly but by installing the correct fan spacer which in affect places the fan toward the radiator closer-the distance was 3 inches closer to the radiator-problem solved