MAJOR Coolant Overflow...Help!

[discoma]

My Discco II has sprung a leak. After the engine reaches temperature, and I turn off the truck, I get a massive overflow of coolant gushing from the overflow reservoir. It seems like once the water pump stops, there's pressure buildup. I've tested for gasses in the coolant and there are none, which leads me to believe it is not a head gasket issue. Previous to this I've had a slow-dripping coolant leak out of the front driver's side bumper. It seems like there might be a blockage somewhere in the system. Is a blocked radiator possible? Any input, ideas or suggestions would be great! Thanks.

[Figman]

Discoma:

I am experiencing a similar problem, My truck is dripping coolant from the overflow hose. is not a whole lot but I know there is a problem there or coming my way. The dealer replaced the radiator some time ago. Recently I began experiencing leak on the system that lead to replace the thermostat and all cooling hoses. Even I replaced the reservoir tank and the cap but still leaking and in three occasions I got the massive gushing overflows. My Indi guy checked (pressure test) in more than one occasion and found nothing. Today, we are testing the coolant with some chemical to see why is the system builing so much pressure that is coming out thru the overflow hose. To my there is a blockage somewhere or there is some type of leak putting pressure onto the cooling system. It is hard to explain but I am going to the same problem.

Good luck

Figman

[ArmyRover]

Blocked radiators have been known to happen...

[bartell]

Originally Posted by discoma

Any input, ideas or suggestions would be great! Thanks.

When you stop the vehicle and turn off the engine, you take the cooling system off-line. That allows the block and rad temperature to increase temporarily. You have seen this phenomena often with other cars when the rad fan comes on AFTER you turn off the motor.

If your cooling is marginal for any reason and can only keep the the coolant just below boiling point, you will boil over as soon as you turn the engine off (after a run).

Flush the engine and rad, fill up with a new mixture (50-50), check for air pockets, check the tightness of your fan belt and change the pressure cap.

If that doesn't work..you may very well be heading for head gaskets.

James