How to change a themostat on a 1991 Ford van?

The radiator is filled with coolant, but the van runs hot.How to change a themostat on a 1991 Ford van?To begin, you should make sure that it is the thermostat, since there are a couple of other problems that can give you the same symptoms. To diagnose the problem yourself, you must have a general knowledge of how the system works. There are 2 necessary steps that must be accomplished to cool the engine. 1. Water flow 2. Water cooling. The thermostat affects the water flow, by regulating it to a particular temperature. The water pump also affects the flow by propeling the water throught the system. One other factor affecting flow is the radiator if it is extremely dirty inside. This will slow the flow of water. The cooling of the water is affected by the amount of air being drawn across the cooling fins of the radiator, and the heat of the air. In other words, you need to find out if you have water flowing through the system when it is at or above normal temperature. If so, do you have air flowing across the cooling fins of the radiator. It could also be a combination of 2 or more things. For example, your radiator is slightly stopped up, and slowing the flow of the water, but with an outside temperature of 75 degrees, the air flowing across the radiator will still keep the temp below 200. Now given that it is now summer, you add the extra strain of running the A/C, plus the outside air is 100 degrees, plus it is now running through a hot A/C condenser before it even gets to the radiator, now it overheats. Just saying make sure before you do it because vans are not fun to work on anyway.How to change a themostat on a 1991 Ford van?You should go to www.autozone.com and click repair guides, if you want the right information it will tell you how to do the jobs.