Lower radiator hose stays cool when top one is hot. and squealing noise on right side by belts

the noise could be steam escaping when over heating from the radiator cap
take it to a radiator specialist shop and have the cooling system pressure tested
could be a cracked tank or a leaking water pump seal

indicates a blocked radiator
The fix is a new radiator
no-- it is not a problem thermostat as the top hose will not get hot if the water is not flowing through the thermostat
yes the bottom hose will get hot but will always be 10-15 degrees cooler than the top hose because the water is being cooled down by the heat exchange from the fins of the radiator
If you switch the engine off the the bottom hose will get hotter to equal the top hose as there is no water circulation from the pump

top hose should be hot, all water from engine goes through upper hose, then radiator to cool and out lower hose.

Sounds like an air lock. There shotld be a release screw on one of the hoses

START WITH THE BASICS. CLEAN, FULL 50/50 MIX IN SYSTEM. CHANGE THERMOSTAT. LOOK FOR TRACES OF COOLANT LOSS FROM THE WEEP HOLE IN BOTTOM OF WATER PUMP (USUALLY UNDER PULLEY). WATER PUMP DRIVE BELT OR SERPENTINE BELT MAY NEED TO BE REPLACED. ALSO MAKE SURE RADIATOR CAP IS WORKING PROPERLY.CHECK FOR LEAKS ANT WHERE ELSE IN ENGINE AREA.

Okay sounds like you have a clog within the system, first of all, drain the whole cooling system, run clean water thought the top of the radiator, look to see when the water comes out nice clear, replace the lower hose if you have a petcock close that, refill the top of the radiator, until it is full, start the engine, with engine running turn your heater, let the car warm a little, then reopen the petcock or loosen the lower hose and let the water draw out a little until is pouring out nice and fast, then re-close the petcock and stop the engine.
try and get 40% of the water out, and replace it with 50/50 antifreeze fill to the right point of the cars specs.

REMOVAL & INSTALLATION
2.0L Engine

1. Disconnect the negative battery cable.

CAUTION Never open, service or drain the radiator or cooling system when hot; serious burns can occur from the steam and hot coolant.

1. Drain the engine cooling system.
2. Raise and safely support the vehicle.
3. Remove the lower radiator hose from the water pump.

If the lower radiator hose is hard to reach on the back of the water pump, remove the hose at the radiator and after the water pump is ready to be removed, pull the water pump away from the engine block until there is enough room to remove the hose from the pump.

1. Lower the vehicle.
2. Remove the accessory drive belt.
3. Remove the timing belt covers and the timing belt as outlined in this Section.
4. Remove the four water pump retaining bolts.
5. Remove the water pump.
   

To install:

1. Thoroughly clean all sealing surfaces.
2. Install a new water pump gasket and the water pump onto the cylinder block.
3. Tighten the retaining bolts to 12-15 ft. lbs. (16-20 Nm).
4. Reinstall the timing belt and the timing belt covers as outlined in this Section.
5. Reinstall the accessory drive belt.
6. Raise and safely support the vehicle.
7. Reinstall the lower radiator hose.
8. Lower the vehicle.
9. Fill the engine cooling system.
10. Reconnect the negative battery cable.
11. Start the engine and top off the coolant as necessary. Check for leaks.

2.5L Engine

Before continuing with this procedure, be sure three new water pump retaining bolts (W701544) are available. Due to their torque-to-yield design, the bolts stretch and cannot be reused.

1. Disconnect the negative battery cable.

CAUTION Never open, service or drain the radiator or cooling system when hot; serious burns can occur from the steam and hot coolant.

1. Drain the engine cooling system.
2. Remove the water pump pulley shield.
3. Remove the water pump drive belt.
4. Remove the water pump inlet and outlet hoses from the water pump.
5. Remove the three water pump to left cylinder head retaining bolts.
6. Remove the water pump and water pump housing from the vehicle.
7. Remove the water pump to water pump housing retaining bolts and separate the water pump from the water pump housing.

To install:

1. Thoroughly clean all sealing surfaces.
2. Install the water pump to the water pump housing using a new gasket and install the retaining bolts. Tighten the retaining bolts to 16-18 ft. lbs. (22-25 Nm).
3. Position the water pump and water pump housing and install three new torque-to-yield retaining bolts into the left cylinder head.
4. Tighten the new retaining bolts to 11-13 ft. lbs. (15-18 Nm), then rotate the retaining bolts 85-95 degrees.
5. Reinstall the water pump inlet and outlet hoses to the water pump.
6. Reinstall the water pump drive belt.
7. Reinstall the water pump shield.
8. Fill the engine cooling system.
9. Reconnect the negative battery cable.
10. Start the engine and top off the coolant as necessary. Check for leaks.

Hope helps (remember comment and rated this).

How to Replace a Water Pump
DIY Complexity: Moderate
DIY Time: 3.5 hours

Parts:
1. Water Pump

Tools:
1. Screwdriver
2. Scraper
3. 3/8 in. Drive Ratchet
4. Cooling System Pressure Tester
5. Needle Nose Pliers
6. Socket Set
7. Radiator Hook Tool

Supplies:
1. Coolant
2. Silicone Sealant

Steps:
Step 1 * With the engine off and cold, open the hood and locate the vehicle’s water pump.
o Tip: Safety Tip:Always wear safety glasses when working on your vehicle. Wear other personal protective equipment (PPE) when necessary, for example latex gloves or safety shoes.
o Tip: Before removing the radiator cap, squeeze the upper radiator hose to verify that the cooling system is not pressurized.

Step 2 * Remove the radiator cap.

Step 3 * Install cooling system pressure tester. Apply the pressure indicated on the radiator cap or in the owner’s manual.

Step 4 * Inspect cooling system components for leaks.

Step 5 * Place a drain pan under the radiator. Open drain valve or remove the lower radiator hose to drain cooling system.
o Tip: Depending on the vehicle, lifting the vehicle may be required to gain access to the lower radiator hose.

Step 6 * Remove the drive belts or serpentine belt.

Step 7 * Remove any hoses connected to water pump.

Step 8 * Unbolt water pump from engine. Remove the water pump.

Step 9 * Using a gasket scraper, clean the mating surface on the engine block.

Step 10 * Install new water pump and new gasket. Tighten bolts to manufacturer’s specifications.
o Tip: You may want to use a light bead of silicone designed for water pumps.

Step 11 * Re-install any hoses and belts that were removed.

Step 12 * Re-install drain plug or lower radiator hose.
o Tip: Squeeze the radiator hose. If it feels soft you may want to replace the hose at this time. Always use new hose clamps.

Step 13 * Refill radiator with a 50/50 mix of coolant and distilled water, then pressure test the cooling system and check for leaks.

Step 14 * Fill overflow reservoir with same mixture.

Step 15 * Leave the radiator cap off, start engine and let it idle. You should see the system“burping” bubbles of air. Refill the radiator to the top.
o Tip: Most air is expelled after a couple minutes of idling. Be cautious of potentially hot fluid overflowing.

Step 16 * Install radiator cap.

Step 17 * Road test vehicle, keep an eye on the engine temp gauge if vehicle runs hot, there still might be an air pocket in the cooling system. The cooling system should be topped off after vehicle has fully cooled down.

Good luck (remember rated this help).

it may be a little off, but the lower water hose seldom gets very hot,, as its this hose that suplyes the engine with ""cold water"" the hot water comes out the top hose,, drains down the rad and cools on the way down then enters the engine through the bottom hose """if your engine stayes running in the normal place on the gage,,,and not over heating""" why are you spending money for nothing???""
you wont get the bottom hose to run hot unless the engine is cooking

My 2005 Nissan Sentra 1.8s with 55,000 mi. blows cold air from the heater. Coolant not circulating in engine. Lower hose stays cool to touch. Both heater hoses cold. Changed thermostat - didn't fix it. Coolant not leaking or dirty. None in oil - no oil in radiator. Changed worn water pump belt - pump spins freely with no noise or resistance. Cooling fans come on after warm-up. Temperature gauge stays in normal range then jumps to hot and back again. Coolant good to 10 below - didn't freeze here yet. No other problems or repairs to car. Afraid to drive and make worse. Help!