Coolant blowing out of radiator after 20-25 minutes.

You m?y have a blown head gasket letting exaust into the cooling system. The pump cannot push exaust. Try a liquid head gasket sealer before replacing gasket. But first open the radiator cap and start the engine. Watch for the coolant to bubble. Top engine and add coolant or water. Some times after doing work on a cooling system you may get air in the system and need to *burp* the systems.

When engine completely cools remove coolant from overflow reservoir to the cold mark on the reservoir which is the lowest mark on reservoir. If you continue to loose coolant you may have busted block.

what would cause the 2001 honda civic to over heat after brand new water pump theromastat timing belt and alternator blet replace yesterday and when it overheated i pulled over and checked all the fluids i had like oil or transmission fluid all over my under part of motor alittle on my breather and top part of hood , the oil also has a tendency to smell like gas but its not oil/gas mixture please help

Vehicles: Any with the above symptoms

A cracked cylinder block will cause either:
(a) motor oil contamination of engine coolant
(b) coolant contamination of motor oil
(c) white exhaust smoke, due to coolant seeping into one or more cylinders.
(d) more than one of the above
(e) all of the above

Oil infiltrating into coolant is easy to see - drain some coolant out through the pepcock at the bottom of the radiator, and place it into a styrofoam coffee cup. Oil droplets floating on top of the green (or orange) coolant are easily seen. Or visualize oil by looking into the top of the radiator through the radiator cap.
Coolant infiltrating into and mixing with motor oil will permanently damage the engine (seizing it up through loss of lubrication), and must be prevented.
A leak from above the front suspension is, as physicians like to put it, "nonspecific", with the most likely cause a water pump seal or hose/hose connection.
A leak from near the fire wall will usually be a heater core hose, or hose connection.
A coolant leak on the same side of the engine as the water pump is a leaking water pump or water pump seal until proven otherwise.

To rule out everythng else, here's the 1999 Honda CR-V Troubleshooting Guide for Coolant Loss/Coolant Leaking:

Priority Action Part Type Cause
1 Inspect Water Pump - Worn, Cracked or Leaking Water Pump, or Water Pump gasket.
2 Inspect Head Gasket - Leaking Head Gasket.
3 Inspect Radiator - Leaking Radiator Hose(s).
4 Inspect Radiator Cap - Worn or Damaged Radiator Cap.
5 Inspect Radiator Hose - Ruptured, Cracked or Leaking Radiator Hose.
6 Inspect Freeze Plug - Leaking Freeze Plug(s).
7 Inspect Intake Manifold Gasket - Leaking, Worn, or Damaged Intake Manifold Gasket.
8 Inspect Water Outlet - Cracked, Leaking or Damaged Water Outlet.
9 Inspect Heater Control Valve - Leaking or Faulty Heater Control Valve.
10 Inspect Radiator Drain Pepcock - Loose, Damaged, or Faulty Radiator Drain Pepcock, or Pepcock O-ring.
11 Inspect Engine (DOMESTIC ONLY) - Cracked Cylinder Block Leaking Coolant into at least one Cylinder, causing white exhaust smoke.

replace the temperature sending unit. Its right there by the thermostat. You can get this at any auto parts store. just need an open end wrench to change it. they do go bad(found out the hard way several years back). I hope this helps you

Water Pump REMOVAL & INSTALLATION CAUTION
Never open, service or drain the radiator or cooling system when hot; serious burns can occur from the steam and hot coolant. Also, when draining engine coolant, keep in mind that cats and dogs are attracted to ethylene glycol antifreeze and could drink any that is left in an uncovered container or in puddles on the ground. This will prove fatal in sufficient quantities. Always drain coolant into a sealable container. Coolant should be reused unless it is contaminated or is several years old. 1.8L Engine

1. Disconnect the negative battery cable.
2. Drain the cooling system.
3. Remove the timing belt.
4. Raise and safely support the vehicle.
5. Remove the engine oil dipstick tube bracket bolt(s) from the water pump.
6. Remove the two bolts and the gasket from the water inlet pipe.
7. Remove all but the uppermost water pump mounting bolt.
8. Lower the vehicle.
9. Remove the remaining bolts and the water pump assembly.
10. If the water pump is being reused, remove all gasket material from the water pump.
11. Remove all gasket material from the engine block. Fig. 1: Exploded view of a water pump mounting - 1.8L engine
    To install:
    
12. Install a new gasket onto the water pump.
13. Place the water pump into its mounting position, then install the uppermost bolt.
14. Raise and safely support the vehicle.
15. Install the remaining water pump mounting bolts and tighten all bolts to 14-19 ft. lbs. (19-25 Nm).
16. Install a new gasket onto the water inlet pipe.
17. Install the two bolts from the water inlet pipe to the water pump and tighten to 14-19 ft. lbs. (19-25 Nm).
18. Install the bolt to the engine oil dipstick tube bracket.
19. Lower the vehicle.
20. Install the timing belt.
21. Fill the cooling system.
22. Connect the negative battery cable.
23. Start the engine and allow it to reach operating temperature. Check for coolant leaks.
24. Check the coolant level and add coolant, as necessary.

1.9L Engine

1. Disconnect the negative battery cable.
2. Drain the cooling system.
3. Remove the timing belt cover and the timing belt.
4. Raise and safely support the vehicle.
5. Remove the lower radiator hose from the water pump.
6. Remove the heater hose from the water pump.
7. Lower the vehicle.
8. Support the engine with a suitable hydraulic floor jack.
9. Remove the right engine mount attaching bolts and roll the engine mount aside.
10. Remove the water pump attaching bolts.
11. Using the floor jack, raise the engine enough to provide clearance for removing the water pump.
12. Remove the water pump and gasket from the engine through the top of the engine compartment. Fig. 2: Disconnect the lower radiator hose (A) from the water pump (B)
    Fig. 3: Disconnect the heater hose (A) from the water pump (B)
    Fig. 4: Remove the water pump's lower mounting bolts (arrows) . . .
    Fig. 5: . . . and the upper mounting bolts
    Fig. 6: After raising the engine enough to provide clearance, remove the pump from the engine compartment
    Fig. 7: Use a scraper to clean the mating surfaces of the cylinder block and water pump
    To install:
    
13. Make sure the mating surfaces of the cylinder block and water pump are clean and free of gasket material.
14. If the water pump is to be replaced, transfer the timing belt tensioner components to the new water pump.
15. With the engine supported and raised with a suitable floor jack, place the water pump and the gasket on the cylinder block and install the four attaching bolts. Tighten the bolts to 15-22 ft. lbs. (20-30 Nm).
16. Install the timing belt and cover.
17. Roll the engine mount into position and install the mount bolts. Remove the floor jack.
18. Raise and safely support the vehicle.
19. Connect the heater hose to the pump.
20. Lower the vehicle.
21. Connect the negative battery cable.
22. Refill the cooling system.
23. Start the engine, allow it to reach normal operating temperature and check for coolant leaks.
24. Check the coolant level and add as necessary.

Water Pump Removal & Installation To Remove:

1. Allow the engine to cool and drain the coolant from the radiator and both engine block plugs.
2. Remove the fan shroud and both radiator hoses.
3. Remove the drive belts.
4. Remove the water pump pulley.
5. Remove the crankshaft pulley.
6. Remove the timing belt covers.
7. Remove the water pump.

Water pump removal/installation

To Install:

1. Install the water pump with new gasket.
2. Install the timing belt covers.
3. Install the crankshaft pulley.
4. Install the water pump pulley.
5. Install the drive belts and fan shroud.
6. Install the radiator hoses.
7. Install the coolant drain plugs.
8. Refill the cooling system.

change water pump

first find out where the coolant is going, do a system pressure test

You're right. it could very well be your water pump, but I would suggest replacing your thermostat before trying to tackle replacing your water pump. However, if your thermostat turns out not to be the problem, I have enclosed step-by-step instructions for removal and re-installation of your water pump. Hope this proves to be helpful. Have a nice evening!


1993 Geo Prism Water Pump Removal/Installation

1. Disconnect the negative battery cable. Drain the engine coolant from the radiator.
2. Remove all drive belts.
3. Support the engine using suitable equipment. Place a wooden block between the jack and engine. Remove the right engine mount and insulator.
4. Remove the No. 3 (upper) and No. 2 (middle) timing belt covers.
5. If equipped with power steering, raise and safely support the vehicle. Remove the front transaxle mount. Lower the vehicle, remove the cooling fan assembly.
6. Remove the mounting bolt for the dipstick tube; remove the tube and dipstick. Immediately plug the hole in the block to prevent fluid from contaminating the oil.
7. Remove the electrical connector for the coolant temperature sending unit.
8. Remove the 2 nuts securing the engine coolant pipe to the cylinder block.
9. Loosen the hose clamp and remove the coolant inlet pipe from the vehicle.
10. Loosen the hose clamp and remove the coolant inlet hose from the water pump.
11. If equipped with power steering, raise the engine and remove the mounting bolts for the water pump. Remove the water pump and O-ring from the vehicle.

To install:

1. Install a NEW O-ring to the vehicle. Install the water pump and torque the retaining bolts EVENLY to 11 ft. lbs.
2. Lower the engine if necessary, and connect the coolant hose to the water pump. Reconnect the engine coolant inlet pipe to the vehicle and secure to hose with clamp and secure to block with 2 nuts. Tighten the engine coolant inlet pipe nuts to 11 ft. lbs.
3. Connect the electrical connector for the coolant temperature sending unit.
4. Install the oil guide tube and torque the retaining bolt to 84 inch lbs. Install the oil level indicator to the guide tube.
5. Install the radiator fan assembly, if necessary.
6. If equipped with power steering, raise and safely support the vehicle. Install the front transaxle mount. Torque the through bolt nut to 64 ft. lbs. and 2 mount nuts to 47 ft. lbs.
7. Lower the vehicle (if necessary) and install the No. 3 (upper) and No. 2 (middle) timing belt covers.
8. Support the engine using suitable equipment. Install the right engine mount and insulator.
9. Remove all engine lifting equipment.
10. Install and adjust all drive belts.
11. Reconnect the negative battery cable. Fill the cooling system. Start the engine and check for coolant leaks.