Engine 5.0 Cooling

my car runs warm in traffic but below warm on the highway.the guy that i bought it from added some stop leak to the radiator.i flushed the system and replaced the radiator, removed the thermostat and noticed that i couldnt see the water circulating and yes the water pump looks new but it wasnt replaced by me.I have an electric fan but no fan stroud the water pump looks like it has already been replaced.So now im wondering could the water pump be messed up due to the stop leak that was added.
 
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From the brief description you gave, I'm not sure what the problem is. In stop and go traffic, or just driving 30-35mph on average, the temp on both my GT and Cobra clone will rise until a bit over half way on the temp gauge, then the cooling fan kicks in to bring the temps down some. But as long as I stay at those slow speeds, the temps will never stay below half way for long. Once I'm on the freeway, my temps are on the far left of the gauge.

What makes you think your Stang is running too warm?
 
A Mustang will naturally run a little hotter sitting in traffic in the summer. Does the car have the original fan on it? You mentioned an electric fan with no shroud. Most aftermarket fans do not have a 2 speed option, or don't push as much air as the stock one. If at all possible, put the stock one back on. Stop leak messes up everything, but there is little you can do about it now. There are ways to make it cool better, but I'm not sure how much money you want to spend.

Kurt
 
Well like I mentioned earlier the thermostat is removed and I can't see any circulation inside the radiator. And on open highway the temperature hand is on the letter N in the word normal and in traffic it moves to the letter M or the letter A but lastnite I read a thread where they were talking about how the air sometimes gets restricted when a car is lowered and mines is very low.So I ordered a twin fan with the aluminum shroud that goes around the both of them. But my main concern is not bring able to see the circulation inside of the radiator with the thermostat removed and new radiator and waterpump looks new also before the guy I bought it from added the stop leak
 
Well like I mentioned earlier the thermostat is removed and I can't see any circulation inside the radiator. And on open highway the temperature hand is on the letter N in the word normal and in traffic it moves to the letter M or the letter A

This is normal. When the temp gets to M or A, the cooling fan should kick in and bring the temps back down between R and M. The fan will turn off and the engine will heat up back to M or A.

You are correct that without the thermostat coolant should be constantly flowing. However, if the water pump was not operating at all for some reason the engine would overheat rather quickly. You certainly wouldn't be able to drive on the freeway for long. fiveohwblow is correct, the best way to test if coolant is flowing is to check the upper and lower hoses as he described.
 
You have to remember that your temperature gauge only gives qualitative readings, not quantitative. Install a 180* thermostat, pour in a bottle of Water Wetter or equivalent, and call it good. If you are really concerned that your engine is running hot, you should get a temperature gauge that will give you an actual numerical temperature value and quit trying to guess what the needle pointing to the "M" means.
 
If both hoses are hard, then the system is pressurizing and coolant is flowing. Without the thermostat, the engine won't heat up easily and it may take a while for the hoses to warm up. With the thermostat in, and when it finally opens, the top hose will be warm - almost hot. Since you've got the thermostat out, you might as well buy a new one. I'd recommend a 180* one (the stock one is 192*, I believe). Any lower than 180* and the engine may not reach normal operating temperature. If you've already put your old one back in, no worries.