My van is over heating there is coolant and water in the radiator it started leaking underneath towards where the front passenger seat

heater core is leaking

Well, if the coolant is leakimg from the HVAC drain, then you need a heater core, no matter what. You really have to jack it up and look, but I can give you a couple of pointers......

1. The water pump is leaking. That happens a lot. The coolant is leaking near the front of the car, near the center, but ever so slightly towards the drivers side. You need a special tool to replace it and I think gm has an updated cover and gasket.

2. The water pump housing is leaking. The gaskets that seal it to the block are made of plastic and deteriorate often. The coolant will be leaking at the center of the car, maybe up by the water pump, or back between the engine and transmission.

3. The heater hoses. I have only seen this 2 time, but the metal pipes corrode along the fire wall.

4. You could need a radiator. I have seen the side tanks leak a few times.....


Just A couple of places to look, but you have to get under and look....

Many Caddys have/had small "radiators" for heat to the rear passengers located under the front seats. Most shops (or owners) never check them or know they exist.

look for a leak from the drain hole under the pump housing, if no leak not a water pump
take the car to a radiator specialist shop and have a coolant pressure test done to determine where the leak is
if it has plastic tanks for the radiator , they split with time and leak under pressure and a pressure test will reveal exactly where the leak is unlike a guess

I'd have to see it in person to comment. The water pump is on the passenger side of the van.
A mechanic would fill the cooling system then pressure test it for leaks.

check all your hoses run vehicle for awhile the inspect hose in this area. look for obvious things next check at the engine to see if a freeze plug is leaking then inspect you heater assembly the core may be leaking I'm leaning toward a hose or shut off valve

It sounds like you still have a leak somewhere, maybe it's a hose clamp that wasn't tightened or another leak. You should check the coolant level in the radiator, not the overflow bottle. If the system has a leak it won't create a vacunm to draw in the coolant from the overflow, the radiator could be very low. The sound you were hearing was air bubbles in the heater corem maybe the coolant wasn't topped off.. If the core was leaking there would be coolant dripping on the passenger's side floor.

This could be a multitude of things:

Stuck closed thermostat.

Cooling fan not coming on.

Clogged radiator.

Low on coolant.

Water pump failing/leaking.

Head gasket blown, leaking exhaust into antifreeze.

Clogged catalytic converter.

Thermostat: If the Van heats up, then feel the upper radiator hose. If it's cold, then your thermostat is closed. Replace thermostat.

Coolant: If low, simply fill with distilled water and coolant. Low levels will let engine over heat.

Radiator: If there are cold-to-the-touch spots on the radiator after it should be warmed up, then a clogged is probably occuring. Have radiator flushed.

Head Gasket: If you smell exhaust fumes in your coolant reservois tank, then you got a blown head gasket.

Cat Converter: Only can be tested if off the car. Or you could try a non-contact thermometer. These are also good to testing cold spot on radiator or if thermostats are open.

Cooling fan: If mechanical it'll be spinning. If electrical, it should come on automatically with the A/C, or when it gets hot.

Water pump: Will be leaking from the front if it needs replaced. On a van, it's a tough job.

Good luck!

I am assuming you are seeing a steam column rising from the outside of the radiator on the passenger side. If this is the case you more than likely have a seam on the radiator leaking. These leaks can be small enough to be hard to detect with the eye. When the coolant leaks out and evaporates from the heat from the radiator it will usually give off a heavy sweet smell. This would defiantly indicate a coolant leak. That is where I would start.

i think its going to be the head gasket duto the way its leaking coolant. one of the water jackets maybe i would have it checked to be sure but it sounds like head gasket