My Alero is overheating, and pushing the coolant out the surg tank, my brother said water pump, changed. then said thermostat, changed. then said radiator clogged, flushed. still doing the same thing?

A worn water pump is the most likely. If the coolant is going down, the water is going somewhere.

The most common reasons an Oldsmobile Alero is overheating are a coolant leak (water pump, radiator, hose etc.), the radiator fan, or a failed thermostat. Coolant leak (water pump, radiator, hose etc.)

Oldsmobile Alero Overheating - RepairPal

Videos on overheating. You probably have air in the system from when you replaced the thermostat. The coolant system needs 'burping' of air.

https://www.google.com/search?q=2000+Oldsmobile+Alero+running+ho

Burping

https://www.google.com/search?q=burping+coolant+system

..

check fans --cooling sensor --relays--check oil for coolant possible intake or head gasket leak

Sounds like a leaking head gasket , or head itself is cracked. If overheating because of sticking thermostat heater would still work. Get it check fast cause next is a blown engine. I guess head might not be torqued properly. Take it back to overhauler and check for oil in your anti-freeze too.

Try looking at all the hoses...AND Water Pump...you should be able to see and verify the leak...hoses etc...the Water Pump is not expensive on your Alero...($35.) Yes, change thermostat at time of coolant drain for Water Pump as needed...:) Hope this helps.

Thermostat Removal & Installation 2.2L Engine To Remove:

1. Remove the exhaust manifold. If equipped with an automatic transmission.
2. Drain the cooling system.
3. Remove or disconnect the following:
   
   
   • Thermostat housing to water pump feed pipe bolts.
     
     
   • Thermostat housing to water pump feed pipe.
   • Thermostat.

To Install:

1. Install or connect the following:
   • Thermostat.
   • Thermostat housing to water pump feed pipe.
   • Thermostat housing to water pump feed pipe bolt.
     1. Tighten bolt to 89 in lbs (10 Nm).
   • Exhaust manifold if equipped with an automatic transmission.
2. Fill the cooling system.

2.4L Engine To Remove:
Thermostat assembly 2.4L

1. Drain the cooling system.
2. Remove the exhaust manifold heat shield.
3. Remove the coolant inlet housing mounting bolts through the exhaust manifold.
4. Raise and safely support the vehicle.
5. Remove the coolant inlet housing stud from the oil pan.
6. Remove wheel and tire assembly.
7. Remove the engine splash shield.
8. Remove the mounting bolts from the transaxle-to-engine block support. Remove the support.
9. Remove the coolant housing pipe.
10. Remove the thermostat.
11. Clean the mating surfaces.

To Install:

1. Install the thermostat.
2. Install the coolant housing pipe.
3. Install and secure the transaxle support-to-engine block mounting bolts.
4. Install the engine splash shield.
5. Install the wheel and tire assembly.
6. Install the coolant inlet housing stud to the oil pan.
   • Tighten to 19 ft lb (26 Nm).
7. Lower the vehicle.
8. Install the coolant inlet housing bolts through the exhaust manifold.
   • Tighten the coolant inlet housing bolts to 10 ft lb (14 Nm).
9. Install the exhaust manifold heat shield.
10. Fill the cooling system.
11. Inspect the system for leaks.

3.4L Engine To Remove:

1. Drain the cooling system.
2. Remove the air cleaner.
3. Remove exhaust crossover pipe.
4. Disconnect the surge tank line fitting from the coolant outlet.
5. Remove the thermostat housing to intake manifold bolts.
6. Remove the thermostat housing outlet and thermostat.

To Install:

1. Install the thermostat and housing outlet.
2. Install the thermostat housing bolts.
   • Tighten the thermostat housing bolts to 18 ft lb (25 Nm).
3. Install exhaust crossover pipe.
4. Connect the surge tank line fitting to the coolant outlet.
   • Tighten the fittings to 15 ft lb (21 Nm).
5. Install the air cleaner.
6. Fill the cooling system.
7. Inspect the system for leaks

there may be air trapped in the coolant system. the fans may not be connected since you had the radiator replaced. bring it back to the mechanic who did the work and tell him your not satisfied.he should be responsible for the discrepany.

Alero, Grand Am 1999-2005 Thermostat - Removal & Installation 2.2L Engine

1. If equipped with an automatic transaxle, remove the exhaust manifold, as outlined in this section.
2. Drain the cooling system.
3. Remove the thermostat housing to water pump feed pipe bolts.
4. Remove the thermostat housing to water pump feed pipe.
   
   
   Fig. Thermostat mounting-2.2L engine
   
5. Remove the thermostat.

To install:

1. Install the thermostat.
2. Install the thermostat housing to water pump feed pipe.
3. Install the thermostat housing to water pump feed pipe bolt. Tighten the thermostat housing to water pump feed pipe bolt to 89 inch lbs. (10 Nm).
4. If equipped with an automatic transaxle, install the exhaust manifold, as outlined in this section.
5. Fill the cooling system.

3.1L Engines

1. Disconnect the negative battery cable.
2. Drain the cooling system to a level below the thermostat housing.
3. Remove the air cleaner assembly.
4. Disconnect the surge tank line from the thermostat housing.
5. Remove thermostat housing-to-intake manifold attaching bolt and nut, then remove the housing.
6. Remove the thermostat.

To install:

1. Clean all gasket surfaces completely.
2. Insert the thermostat in the intake manifold.
3. Attach the thermostat housing to the intake manifold.
4. Install the mounting bolt and nut. Tighten to 18 ft. lbs. (25 Nm).
5. Install the air cleaner assembly.
6. Connect the surge tank line to thermostat housing.
7. Refill the cooling system.
8. Connect the negative battery cable, remove the radiator cap, then start the engine. Allow the engine to run with radiator cap removed, until the upper radiator hose becomes hot (thermostat open). With the engine idling, add coolant to the radiator until the level is up to the bottom of the filler neck.
9. Install the radiator cap, making sure the arrows line up with the overflow tube.

3.4L Engine

1. Drain the cooling system.
2. Remove the air cleaner.
3. Remove exhaust crossover pipe.
4. Disconnect the surge tank line fitting from the coolant outlet.
5. Remove the thermostat housing to intake manifold bolts.
6. Remove the thermostat housing outlet and thermostat
7. Clean the mating surfaces.

To install:

1. Install the thermostat and housing outlet.
2. Install the thermostat housing bolts. Tighten the thermostat housing bolts to 18 ft. lbs. (25 Nm).
3. Install exhaust crossover pipe.
4. Connect the surge tank line fitting to the coolant outlet. Tighten the fittings to 15 ft. lbs. (21 Nm).
5. Install the air cleaner.
6. Fill the cooling system.
7. Inspect the system for leaks.

Hope this help (remember comment and rated this).

in order to replace the thermostat u either have to remove the exhaust pipe on the left side of the engine (driver) or the lower intake but them engines are known for then lower intake gasket leaking and if you are loseing coolant then i would look in to haveing the intake gasket checked

If you changed the hoses and thermostat and the car is still overheating, then the next thing to look at is the water pump. See if the water pump is leaking water from a vent hole. If it is, then the water pump is defective and will need to be replaced. Sure hope this helped.

if one radiator hose gets hot and the other doesnt, the the thermostat is shot, but you said you replaced it, it is possible the thermostat has been put in backwards