Chevrolet Repair: 95 S-10 Overheating, upper radiator hose, fan clutch

Question
Van,

About 2 weeks ago my water pump went.  I put a new pump in and since then it has been overheating.  I thought that maybe I did not put in enough anifreeze/water so I flushe the system and put the correct mixture back in.  Still overheats.  I put in a new thermostat,  still overheats, put in a new fan clutch as the other was going.  Now before this all happend the truck was running great.  I do live in FL.  and yesterday driving to Soccer it over heated but in the same distance comng home at 11:00pm it did not it stayed at the normal temp.  

Any thoughts or suggentions.

Thanks

Rob

Answer
Hi Rob,
Sometimes a pocket of air trapped in the engine can be real hard to burp out, and can cause what you have.
Another thing to make sure of is the pump is the correct one.
Then make sure it is circulating coolant. I would first drain and catch the antifreeze mix in a clean container to reuse later, and fill the system with water. Remove the thermostat, but bolt the thermostat housing back on, and have the hose off the radiator, probably pointed out over the grille. Stick a garden hose into the hose connection of the radiator, or the cap opening, and have the water running. Start the truck for a few seconds to see if it pumps a large amount of water out the radiator hose.
If it looks like the pump is working good, and pushing the water in the correct direction, drain the system, remove the thermostat housing, but before replacing the thermostat, start filling the system with coolant.(May want to have the upper radiator hose back on the radiator neck.
Add the coolant till the thermostat housing has coolant filling the hole.
Then put the thermostat in, and bolt the neck on.

Make SURE the thermostat is installed in the proper direction, or it won't open properly.
The big sensing slug and spring need to be submerged in the coolant in the manifold.
I saw one just today that the person had it in backwards. It will overheat, but if allowed to sit for an hour or so while hot, could actually open, and seem normal, till allowed to cool way down again.
Actually, that sounds like what yours did around the soccer practice.

That filling method above will reduce the possibility of an air pocket.

Van