Water blowing out of over flow after turning engine off.won't recover coolant.has new cap & radiator.no sign of exhaust gasses in radiator when using head check.Mitsubishi magna 2.6lt 1992 tr

Blocked radiator, have it serviced.

More likely than not, you have done damaged the engine! Try this, with engine cold, remove radiator cap/coolant jug. Fill with water to proper level and leave cap off, then start engine. If the water/coolant goes immediately to gushing out that means you are getting compression from 1 or more of your engine cylinders into the cooling system from the heads or head gaskets being blown.

Also, depending on which engine your car has, (3.4L or 3.8L V-6) if 3.8L engine, they are know to get cracks in the plastic intake around the EGR valve area. Either way, as I'm sorry to say more likely than not, you'r engine has already suffered internal engine damage which can be very costly to fix.

If you know how, you can perform a compression test to determine which cylinders are damaged. But, if you are getting water/coolant in ANY of the cylinders, do not drive/run the engine as it will only get worse and cost more to fix. I hope this helps

Possibly leaking head gasket. Easiest way to check would be to fill radiator full, start engine and watch coolant level in the radiator cap opening. The top radiator hose will become hot when thermostat begins to allow coolant flow through the radiator. You may have to top off the coolant. Still with the radiator cap off watch for water belching out of the radiator neck. If coolant does belch out of the radiator cap neck, refill with water. If it belches out coolant again it would be combustion gassed forcing the coolant out of the radiator.


This process should take about 1/2 hour to diagnose if it is a head gasket leaking combustion gasses into the coolant.


The radiator fan may run once car is shut off to cool engine compartment to prevent gasoline in fuel lines from vaporizing which would cause a condition called "vapor lock". A car won't start if fuel lines are vapor locked.

Good luck, I hope this helps you to figure out the problem.

Have you pressure tested your rad cap? It may not be holding the proper pressure. Also, is the rad in good shape? Are the rad fins in good shape & is the coolant in the system circulating properly. It is possible the new water pump impellor is slipping. When engine is cool, take rad cap off & start the engine. Check for coolant circulation in the rad when thermostat opens. Is it flowing freely without restriction? Top off the coolant again , you may have a vapor lock. Hope this helps. Good luck!

Hi, its not good news im afraid by you describing that with the coolant cap off and revving the car causes the pressure to build up and push the water back out it sounds to me like the head gasket is on its way out, what you need to do is take it to a garage and dont have a compression test done you need to have a gasses test done, you can buy these yourself if you want to and what it does is this.

its a plastic tube with blue liquid inside it then you take the coolant cap off and place this in its place you then run the engine and rev it up then you squeeze the rubber at the end of the tube and it then sucks the air out of the coolant and through this liquid then if it detects gasses from the engine in the coolant then this turns the liquid green and this is then telling you that the head gasket needs changing.

please dont let it keep over heating as this will cause the cylinder head to warp and you would then need to get it skimmed to make sure its not warped, get the gasses test done as a compression test dont give you a true reading as the engine is not running when they do a compression test.

let me know how you get on or if you need further assistance ok

plz rate this solution as i have a whole page of unrated posts, thanks

well look at the fuel consumtion and the power it has while driving... if it is getting low mpg and it has low power than i would say that the timing is off . it is probably to far advanced and no matter what you do to keep it running cool it wont... and does it run hot going down the road or sitting still. if it is running hot while going down the road and the timing is right. your radiator should be cleaned ( the out side) if it is while it is sitting still check see if the fan is even coming on.

It sounds like you have air on your cooling system, recheck the coolant level at the radiator cap. "engine cold" Make sure the radiator is filled to the top and add if needed, place the radiator cap back on only at the first click and make sure the over flow tank is at the full level and start up the engine to warm it up with the heater on high heat. If you like you can go for a 10 min drive to ensure the thermostat has opened and all the coolant has cycled through out the engine and heater core. With the engine still running, close off the radiator cap to the second click and then turn off the engine, this should have worked the air out of the system. If not do it again and keep en eye on the over flow tank, top off if needed. Good luck and hope this helps. 

With cool engine... open radiator cap and look inside radiator. Do you see lots of sediment and calcium growth on radiater tubes? If yes, a coring may be needed. If only slightly bad, a radiator flush may be needed... then refill with 50 percent antifreeze.

Good thermostat, cleaned cooling system, non-leaking water pump, good water flow via water pump... nothing else left (unless you put the thermostate in backwards)..

Let us know

Hello there.....

First things first: Is the temperature gauge showing normal as it is supposed to be? No contamination of oil & water on withdrawing the oil dipstick? Head gasket not the culprit here? No excessive steam on idling from the exhaust system? If these signs are not present than I suppose there could be an air lock within the cooling system - bleed the system - check if the radiator/coolant reservoir cap is satisfactory. Top up the radiator (if possible) with mixture of water & antifreeze whilst the vehicle is idling. Hope this helps.

Good luck

Your message is listed along with 2000 DeVilles - not gonna get much feedback that way -
Even though you don't have visible water coming from the exhaust, the combination of overheating and coolant loss still sounds like a blown headgasket.
When the engine is running, you are pushing exhaust gases into the cooling system and producing heating of the coolant the radiator can't handle. When the engine cools down, you are probably sucking a little coolant into one or more cylinders.
Tie an old towel over the tailpipe before starting the cold engine to see if the exhaust gases are as dry as you think.
Depending on how bad or where the head gasket is failing, watch for any oily signs in your coolant, any signs of engine oil turning into hand creme and with a cold engine, take the coolant fill cap off, then start the engine allowing it to warm some and watch your coolant overflow bottle for bubbles. If you find any of those signs and are still not convinced, pull each plug and look for signs of rust on the plugs. If you find it, well . . . Any or all of the symptoms above say 'blown headgasket.'