How would I go about doing a cooling system test ?
my 89 arostar V6 3.0 is running a Little Hot... & I would like to know all the Things to (Check/Fix) to get the cooling system back to %100 !!!

 

Check make sure radiator is clean on the outside and make sure that the condition is good on the inside. Thermostats can quite often go bad on the Aerostar and radiator hoses can collapse. Make sure that the radiator cap holds the recommended pressure. The fan clutch sometimes requires replacing and I've seen a lot of the plastic fans actually missing pieces or even blades, although this probably applies more to the 4.0 engines. I've even seen water pumps missing a few impellers. Good luck.

 

If you find that your coolant level is a little low try squeezing the hoses usually if there is a leak the pressure will cause coolant to come out. That was the case on my Aero only when the engine was on or I squeezed the hose would it leak since it was a pinhole leak.

If you really want to get technical you can buy a pressure pump that attaches to the radiator cap. You attach it and pump it similar to the old fashioned up and down bicycle pumps a gauge will read out the pressure if it drops then you have a leak.

If you can't find any leaks after the visual inspection of the radiator I would replace the thermostat and the gasket.

The thermostat is just below where the upper radiator hose meets the engine loosen the the 2 bolts and remove the nipple. At this time carefully scrape the old gasket off of both the nipple and the block. I used a putty knife since its thin and flexible. Pay attention to which way the thermostat is inserted if you insert the new one backwards it can cause trouble.

If you can't remember the last time you changed your coolant it could also be that your radiaitor is clogged and it needs to be flushed. To check put a small container under the radiator and open the drain valve to let a little bit of coolant out. If its brown instead of green or orange then you definately need a flush.

When my Aero was overheating it was due to a leak however since the coolant was brown I did a flush and replaced the thermostat as well still running great here.

 

If you flush your cooling system with that Prestone flush kit, where you install a garden hose adapter to the heater hose, you can adapt a bicycle pump to it to make a pressurizer. I cut the valve out of an old inner tube and drilled a hole through a hose cap for it. I cut the tube material so that it will fit properly into the backside of the cap for a tight seal. Then just attach the bicycle pump and pump away. The system will take some air before pressurizing, and the first thing to give should be the radiator cap at its rated pressure.