I have just replaced the radiator in my c70 volvo and now the water/coolant is not rotating through the upper hose until the car gets hot and than the water spits out. Could this be my thermostat?

If it over heated before the thermostat, replace the radiator cap. Make sure the coolant (recommend just water until this is fixed) is full. When disconnecting the upper hose you lose all the coolant from the engine and about 1/3 of the coolant in the radiator. If you only full the radiator you don't have enough water. The new remonstrate needs to open for you to get enough water. In short- take radiator cap off. Start the engine. Fill radiator. Watch level for 5min, filling as needed.

replace thermostat.then bleed coolant system, this is how you do it.fill the cooling coolant system with 50 / 50 dexcool and water to raise boiling point,straight water will evaporate boil away cause engine to overheat catch fire thats why you need 50 / 50 mixture antifreeze and water.to bleed coolant system first fill coolant system until coolant stay at the full cold mark on the the coolant overflow jug,then you start engine allow it to idle,place the heater and ac control in any ac setting except max and the temperature control to the highest setting,run engine until lower hose to water pump is hot. with the engine hot run the engine speed up to 3000 rpm and allow it return to idle, repeat this 5 times. slowly open the bleed valve on the thermostat housing or look for bleed valve at the water pump heater hose.open bleed valve for 15 seconds to expel any trapped air.then top off the coolant as necessary,and when top radiator hose hot thermostat open up.keep adding cooling to overflow until coolant level stop at full cold mark dont over fill coolant.if engine seem like overheating while looking at cooling gauge turn off engine wait a while until cool off add more coolant until coolant level stay stable and dont drop any.when open radiator overflow cap use large rag over the radiator cap to keep from getting scald open radiator cap a little at a time but dont open radiator cap until engine cool down first.replace the radiator overflow cap, thermostat,and engine coolant temperature sensor and check the cooling fans fuses and relays see what happens.

If the system fills via an expansion tank, I would recommend removing the top hose from the radiator and filling the system by pouring the coolant in through the hose until it begins to flow out of the upper radiator port. Reconnect the hose and then fill the expansion tank. That should take care of it.

you still have air trapped in the cooling system. Get front of car as high up as you can on a hill. Cold engine - loosen radiator cap, fill with 50/50 antifreeze mix. Start engine and run until upper radiator hose is hot (thermostat open). Engine should burp air and maybe spill some coolant, that's ok. Once burped, tighten cap, shut off engine and let it cool down while keeping the reservoir full. It will **** coolant out of reservoir as it cools. Keep it full.

If still cold air, take to a shop that has evac/fill equipment; they will **** air out and repalce with coolant. About $80.

gerry

Wait for th engine to cool off then remove th radiator cap and let the engine run until it shows signs of getting hot. If you can't see the coolant flowing in the radiator then the thermostat is not opening or there is no coolant in the radiator. Make sure the radiator is full. If that doesn't help then replace the thermostat.

The F-350 designation refers to a 1-ton Ford F-Series pickup truck. The thermostat in your diesel-powered Ford closes off the flow of coolant when the engine is cold, forcing the engine to heat up faster. When the coolant has reached a certain temperature, the thermostat opens up and the coolant flows as normal. A malfunctioning thermostat in your diesel may cause your engine to overheat if the thermostat gets stuck in the closed position. Installation of a new thermostat will cure the problem and get you back on the road

Open the hood. Allow the motor to cool off so that you will not be scalded by hot coolant. Locate the thermostat housing by tracing the upper radiator hose from the driver's side of the radiator to its termination at the thermostat housing.

2 Remove the cap from the white plastic coolant bottle at the front of the engine bay. Place a drain pan under the radiator drain petcock on the lower side of the radiator on the driver's side of the truck. Remove the petcock by rotating it counterclockwise with a 19mm wrench. Replace the petcock and tighten it in a clockwise direction once the coolant has fully drained.

3 Remove the clamps from both ends of the upper radiator hose with a pair of pliers. Pull the hose from the radiator and from the thermostat housing, using a twisting motion. Set the hose and clamps aside.

4 Spray penetrating fluid on the three mounting bolts on the thermostat housing and let it soak in for a few minutes. Remove the three bolts with an 8mm wrench turned counterclockwise. Remove the thermostat housing from the water pump and set it and the bolts aside.

5 Remove the thermostat housing from the water pump to reveal the thermostat. Carefully pry the thermostat up with a flat-blade

screwdriver if necessary. Clean the mating surfaces on the thermostat housing and at the water pump with a rag.

6 Place a new thermostat into the water pump with the pointed end facing upward. Install a new O-ring gasket into the groove on the thermostat housing mating surface of the water pump. Position the thermostat housing back onto the water pump and tighten the three bolts with a torque wrench to 15 foot-lbs.

7 Push the upper radiator hose back onto the radiator inlet and the thermostat housing until it is fully seated at both ends. Replace the hose clamps in their original position with a pair of pliers. Refill the coolant that you drained from the radiator back into the white plastic coolant tank and replace the cap. Start the engine and let it warm up. Check for leaks and retighten your connections if necessary

Upper Radiator Hose and Thermostat

A large part of a radiator's function is made possible by the upper and lower radiator hoses. The upper radiator hose controls the flow of engine coolant from the radiator into the car engine. In a cold engine, engine coolant is stored inside the radiator. The engine coolant is held inside the radiator until the engine becomes hot enough to warrant engine coolant circulation. When an engine reaches operating temperature, the thermostat valve, which is located at the far end of the upper radiator hose, opens up and allows engine coolant to flow from the radiator into the engine.

Volvo 1990-1998 Repair Guide
Radiator - REMOVAL & INSTALLATION
Perform this work only on a cold engine.

1. Disconnect the negative battery cable.
2. Set the heater control to MAX heat.
3. Remove the expansion tank cap.
4. Place a suitable drain pan into position. Open the **** on the right-hand side of the engine block. Fit a hose to the **** to collect the coolant. Open the radiator draincock.
5. Close the drain cocks when the coolant is completely drained.
6. Remove the cooling fan.
7. Remove the cooling fan shroud.
8. Disconnect the upper and lower radiator hoses

9. On vehicles equipped with automatic transmissions, disconnect the transmission oil cooler lines at the radiator. Plug the lines immediately. Catch the spillage from the radiator in a separate pan.

10. Some vehicles are equipped with a temp sensor on the drivers side top of the radiator, if equipped remove the connector.
11. Remove the radiator retaining bolts and brackets.
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12. Remove the radiator assembly from the vehicle.

On 850/C70/S70/V70 models, the radiator comes out the bottom of the vehicle.
To install:

1. Place the radiator into position and install the retaining bolts.
2. On automatic transmission vehicles, connect the oil cooler lines.
3. Install the fan and shroud.
4. Install the lower and upper radiator hoses.
5. Connect the expansion tank hose. Make sure that the overflow hose is clear of the fan and is free of any sharp bends.
6. Fill the cooling system through the expansion tank, with a 50 percent antifreeze, 50 percent water solution.
7. Connect the negative battery cable.
8. Run the engine until normal operating temperature is reached.
9. Bleed the cooling system.
10. Check for leaks.
11. Top up the cooling system, as required.
12. Replace the cap.
13. Check and top up the automatic transmission fluid level.

Hope thats help (remember comment and rated this).

This is how I like to do it. Make sure the car is parked with the front end at an upward angle. Drain the coolant from the petcock at the bottom of the radiator. Remove the upper and lower hoses at the radiator. Remove the thermostat housing, and the heater core hoses at the fire wall. Flush out the radiator by pouring fresh water into the overflow, and the hole where the thermostat was. Flush the heater core as best you can by pouring fresh water into the heater core hose connections.
Let all the water drain out, then button everything back up and replace the thermostat with a new one. Refill the rad and engine by filling the coolant reservoir with a mix of 50% water and 50% antifreeze, or buy the premixed stuff from the auto parts store. (Buy 4 jugs of premix or 2 of straight antifreeze)
Run the engine until it reaches operating temperature and the upper rad hose gets hot. Rev the engine a little to help get the air out of the cooling system. When the thermostat opens, the coolant level will drop in the reservoir, so top it up and replace the cap.
Check for leaks, and check the coolant level for the next few days, and check for leaks.
Dispose of the old coolant responsibly

make sure engine is cool then drain coolant by opening the drain plug at bottom of radiator. remove cap from radiator so coolant will continue to drain and when coolant is down enough to pull off upper radiator hose at intake then close drain, then remove two bolts at coolant housing and remove thermostate. clean gasket material from intake and housing and replace with new gasket and thermostate tighten bolts install hose fill rad with coolant water mix 50/50 and run engine with heat on floor until gets hot and you see coolant flowing in rad, install cap