Water shoots out of expansion tank and overheats, electric fan no

no year car told, age matters on all machines. all.
all cars run about 15psi , pure physics of hot water expansion and cap pressure regulated.
my guess is you mean the overflow tank on side of RAD,that has exploding steam and water to this side tank? "violently" that be gross overheating
lots of causes and lots of tests. to find it.

• bad thermostat ,10 years is like max. life.
• dead water pump.
• bad radiator
• bad RAD fan. dead. or dual fan 2nd is dead.
• low coolant, sure,after now but is no cure filled and tried. full up in rad dead cold 50%AF MIX.
• FANS BELT MISSING OR LOOSE. (TO PUMP)
• BLOWN HEAD GASKET OR WARPED HEAD(S) CAUSED.
• SIDE TANK HOSES BAD MORE MISSING SUCH THE EVERY COOL DOWN AF DOES NOT GET SUCKED BACK INTO RAD. MAKING IT DROP LEVELS OVER TIME.
• ALL WATER HOSES CAN LEAk or heater core. causing water loss and bingo overheats.

overheating has many symptoms, not just green on the ground
do tell?


temp gauge lies its buns off... use a real tool called a thermometer to see real temps. we use a IR pyro gun to see it and not GET burnt.

gauges is telling truth, so......................


a bad rad cap, or bad thermostat are common fails.
test one: (dead cold engine) never hot.
radiator tank filler cap off , you look down there, is the level really low?
(forget the silly side expansion tank for now)
if found low , then fill it and burp it. no air allowed there
running 50% antifreeze now? no?, that its WRONG.
the tool is $2, test it. (Prestone sells it)
the coolant is all rusty color, (ill not comment ) try service.

1. Green on the ground,? for passengers feet.
   
2. Water exploding from overfill side tank? ( oil in RAD or Milky engine oil) (same milk in transmission pan?)Exploding gases, on cold start is bad head gasket or warped head or cracked head/block, or just simple overheating, The Rad leak down test and the exhaust test (green/blue ) tests solve this riddle easy.
3. Steam rising from hood or Radcap, or hose to Cap and recovery tank. Over heating or leaks.
4. Dash gauge pegged. (or WILD GAUGE swings "air pockets below thermostat") or gauge bad. sender bad.
   
5. Motor pinging and loss of power. (do not allow pinging, it will wreck the engine)
6. Pistons landing on ground? (just joking....)
7. A/C dies?, does it?, due to A/C engine overheat switch ,tripping off. a 235 ?F (spec) see FSM. A/C means Air conditioner clutch dead.
8. Does the engine over heat , if left idling a long time (30min-1hr). or only at stop signs or red lights? (clutch fan not activating , check it, this way.)
9. Does it only over heat while moving ? ( a bad pump, or Rad)
10. Overheats, only on hills? (bad RAD)
11. Only overheats pulling heavy loads ? (inside, full of bricks, or pulling a 1000 trailer ? ONLY?
12. Never overheats moving fast on flat ground. (so the RAD fan is dead, no mater if stock or hacked in electric fan, it's DEAD)
13. Do you have carbon or oil floating around in the Rad, filler CAP neck top tank ? yes?, that is bad head gasket or worse cracked block/head. Do the Exhaust test.
14. Overheats under all conditions, Catastrophic overheat. ( can be bad pump (rotor gone) or RAD or system is packed up)
15. Seems to overheat , even at first start , in 1min or less I have gases shooting into the overfill tank, that is a bad head gasket (mostly a warped head, at least)
16. Antifreeze (and water) in the pans, Engine or Transmission.
17. The RAD fan is DEAD ( just because a mechanical RAD fan coasts, don't mean it WORKS RIGHT.) See the clutch tests below. if electric fan , there is a test in the FSM covers this 100% the fan must come on over heated,.
18. my electric fan , starts to run idling engine long time at 225F. It kicks on, some cars have 2 fan and staged, come on trip points.
19. RTM read the manual the FSM>
20. there is more im sure, cant think of them all now.

That pyro gun allows me to test any RAD easy , ask.
ok , i check all rad tube top and bottom and bingo find any tube clogged fast. if all are equally clogged.(partial) i cant find that.
that is caused by zero service, so...and there are signs for that too.

There's trapped air in the cooling system.

• You need to remove the bleeder screw on top of the radiator when adding water to the expansion tank.
• With the engine running, pour water into the expansion tank till you see air go out through the bleeder screw's hole.
• Just keep adding water until no more air bubbles come out then just put the screw back in place.
• Then fill the expansion tank to it's normal level/line.

Mr. Johnson,just for your information a car to overheat is not only fan and radiator,there are more things like the below I will state and check.
THERMOSTAT whether stayed close,WATER PUMP might the propeller is worn and does not circulate the water,- to confirm about is to start the car without thermostat but full of water and rev it at about 1500 rpm and follow the expansion tank whether the water circulates.- RADIATOR FILLER CAP whether is the correct with the manufacturer recommended pressure, MATRIX whether is open and allow water to circulate-check the hoses of it whether are getting hot similar to the radiator heat hoses.RADIATOR is it clean inside from any mud-check the vents outside having the engine off and touch all the surface- must have the same heat allover the surface.EXPANSION TANK hose connected with radiator whether is open and not blocked to allow water to move.FINALLY if everything is okay and you still have the same problem then is unfortunately either compression gasket or cylinder head.One last advise `before you go for the worst please check also your valve clearance whether valves are not tight and forcing the engine on driving.Good Luck and let me know what happened.

hello my8,
First confirm that the engine is actually overheating - steam, no heat to the interior etc. Sometimes a temperature sensor will fail and give a misleading 'overheat' reading on gauge. For that matter sometimes the gauge can fail and give the same misleading reading. Check that the cooling fan comes on when the engine temperature starts to rise above 'normal'. If not check (in order) fan fuse, fan relay, fan sensor, fan. Real overheating is caused by a lack of coolant AND/OR lack of coolant flow. Modern cooling systems are 'closed'. In other words there should be little or no loss of coolant. If the level is significantly low you have a leak....either external or internal. With the coolant topped up to the correct level and the radiator cap on, run the engine and look for visible leaks...hoses, valves, radiator etc. Internal leaks, eg. head gasket will usually be accompanied by white exhaust smoke (steam), hard starting, rough running and bubbles in the expansion tank. Sometimes, though NOT always, you will fiand the engine oil has a milky look and/or engine oil will be mixed in with the coolant.

Lack of coolant flow can be caused by anything in the system that causes an obstruction......in order of common occurance......thermostat stuck closed, radiator blockage, heater core blockage, water pump failure. One last point. because of design considerations many vehicles have the radiator mounted at a different level than the uppermost coolant passages in the engine thus trapping air in the coolant passages. In short the system must be bled of air in order to properly fill with coolant. Such systems will incorporate bleed screws usually in either the top/side of the radiator, the top hose, the thermostat housing and sometimes in all of these points. To bleed out the air do NOT run the engine as you fill the radiator. Instead, open all bleed screws. As you fill the radiator coolant will run out of one or more bleed points. Close this bleed point(s). Continue to fill until coolant escapes from the next bleed point then close that one. Proceed until coolant has escaped from ALL bleed points then continue to fill to the correct level. The expansion tank will have minimum and maximum level markings. Fill only to the minimum level mark with the engine cold.

hope helpful,
greetings

Do you have an overflow tank that has low level in it?
LEVEL CHECK The coolant level should be checked regularly. Serious engine damage can occur if the engine overheats. CAUTION
Check the coolant level when the engine is cold; serious injury could result from escaping steam or hot fluid if checked when hot. If your car is equipped with an electric cooling fan, make sure that the ignition switch is OFF. The cooling fan will automatically operate if the ignition switch is on and the engine coolant temperature is high, or if the wiring connector on the thermostat housing is disconnected.

1. Depress the button on the thermal expansion tank (coolant recovery reservoir) safety cap, if there is one. Allow all of the pressure trapped in the system to escape. CAUTION
   The radiator is not factory-equipped with a safety cap. Do not remove the radiator cap before removing the expansion tank cap, or when the engine is hot. Fig. 1: Remove insects and debris from the radiator fins
   
   
2. Remove the expansion tank cap. The expansion tank should be 1⁄3 full, unless Full and Low marks are provided. The level should be well above the bottom of the tank when the engine is cold.
3. If it is not, carefully remove the cap from the radiator. The radiator should be full.
4. Add a 50/50 solution of ethylene glycol (or other suitable coolant) and clean water. If there was no coolant in the expansion tank, fill the radiator until the level is near the inlet port and install the radiator cap. Then, fill the expansion tank to the specified level, and secure the expansion tank cap. When checking the coolant level, the pressure cap should be examined for signs of age or deterioration. Check it for a worn or cracked gasket. If the cap doesn't seal properly, fluid will be lost and the engine will overheat. A worn cap should be replaced with a new one. The fan belt and other drive belts should be inspected and adjusted to the proper tension. (Please refer to the belt inspection and adjusting procedures, earlier in this section.) Remove the radiator cap and run the tip of your finger around the inside of the filler neck. Check for excessive deposits of rust or scale around the filler neck lip and the filler port. Make sure the coolant is free of oil. Replace the coolant as necessary. Hose clamps should be tightened, and soft or cracked hoses replaced. Damp spots, or accumulations of rust or dye near hoses, the water pump or other areas indicate possible leakage, which must be corrected before filling the system with fresh coolant. Periodically clean any debris, leaves, paper, insects, etc. from the radiator fins. Pick the large pieces off by hand. The smaller pieces can be washed away with water pressure from a hose. Carefully straighten any bent radiator fins with a pair of needle nose pliers. Be careful as the fins are very soft. Don't wiggle the fins back and forth too much. Straighten them once and try not to move them again.
   

There could be a couple of reasons for this,

1. The thermostat could be stuck closed creating more pressure than normal. Your temp guage would show a higher temperature or you have another blockage in the system.
2. The expansion tank is too full.
3. The cylinder head may be leaking. If you fill the system run the engine to normal temperature with the radiator cap off, look for quite large bubbles coming out of the filler cap. If the head is badly leaking, they can be like a volcano. The temp will rise quickly from cold and the engine will overheat in a short distance.
It does seem odd that it would only spill over after 20 mins. Suspect that the expansion is over full first if your temp is normal. Let it run until it stops and see where the level is when the engine is cold.

We have had some similar problems with some BMW's,the last one we replaced the expansion tank.Before we attached the upper radiator hose to the radiator we filled the engine with antifreeze through the hose.Install the hose and fill your expansion tank to the proper level and run the engine to operating temperature.

make sure you have 50 percent water and 50 percent antifreeze.hot wire fan to see if work.if not replace it.if works check fan relay.if car stills over heat check top radiator hose .should get warm in 10 minutes.if not replace thermostat. if a lot of white smoke come out of exhaust.after car warms up .suspect blowed head gasket.

hi it sounds like your headgaskets blown you need to take your rad cap off fill with water start the engine see if you see any bubbles in the water or if the water blows straight out its a good indication the headgaskets gone the thing on the right hand side is the expansion tank overflow if this blows water out even when cold the headgaskets gone if you see no bubbles in the water change your thermostat the two fans on the rad have nothing to do with your a/c if that doesn,t work may need pressurising yates210456