2000 grand caravan mystery coolant loss

[rykerjenbob]

In less than 5000 miles I've lost an overflow tanfull of coolant. Bought the van used from a chrysler dealer and have taken it back there twice only to be told they can't find anything. Going back for the third time next week. If they can't find anything what legal recourse do I have? My major concern is that this is a precursor to something bigger and I don't want that thing to breakdown with 3 small children in it. Unfortunatley the lemon law won't apply but what else should I do?

[Ghostman]

Coolant lose brings three things to mind, 1. it is leaking externaly and you will see evidence of that on the ground. 2. it is leaking at the heater core and that will put coolant on front passenger floor area. 3. the engine has an internal leak and it is in the oilpan or it is being burned with engine conbustion (head gasket), this will show up as white smoke at tailpipe and smell funny.

[gforster]

go to another dealer and tell them to pressure test the system... this will surely reveal the problem. That is such a slow consumption I'm thinking very small leak somewhere. A head gasket leak will usually get worse very quickly. Check the radiator tanks as well for small hairline crack (undetected collision damage) I had this problem with my 96 it was a slow leak and hard to find - it was not even dripping on the ground.

[swk1219]

Originally Posted by rykerjenbob

In less than 5000 miles I've lost an overflow tanfull of coolant. Bought the van used from a chrysler dealer and have taken it back there twice only to be told they can't find anything. Going back for the third time next week. If they can't find anything what legal recourse do I have? My major concern is that this is a precursor to something bigger and I don't want that thing to breakdown with 3 small children in it. Unfortunatley the lemon law won't apply but what else should I do?

You may have a head leak or a leak in the coolant supply tube to the water pump. If the engine is a 3.0 (I'm not sure if the other v-6's are like this as the 3.0 is made by Mitsubishi) the water pump suction is from a tube that runs in the engine V under the intake manifold. The return hose from the radiator connects on the right side near the transmission and this tube runs underneath the intake manifold to the water pump inlet/suction. The tube is very thin walled and it is kept in place by the water pump and o-rings. The tubes can leak because of an o-ring failure from overheating. They can also rust at the o-ring land which is what happened in my 3.0 (130,000 miles). The fix is to dismantle the engine and try to determine if the tube is leaking. If not, then you probably have a head gasket leak and the heads will have to come off. It is worth the effort to get a valve job and new valve seals if you go all the way to taking the heads off. I would recommend actually removing that tube and checking it. The part that rusted out on my engine wasn't visible while the tube was installed. I ended up with the leaking tube and a head leak. The leaking tube is on the suction side of the pump, so with the cap off it will look like air is bubbling up through the coolant. It will also overheat at idle because the air will cause the water pump to lose suction and the water will quit circulating. You can feel it with the heat on in cold weather. At idle and low speeds the lack of circulation will make your heater go cold. As you speed up the engine circulation will improve with higher engine rpm and the heater will start to blow warm air. The problem will leave you on the side of the road so make sure to get it fixed. It will also ruin your engine from overheating and may cause a head gasket leak. The coolant loss from the tube may go into the crank case. A way to tell this is to pull your air filter and check the area below the air filter. There is a crank case vent tube that runs into the bottom of the air filter housing. Just above on the inside of the housing is a white foam cushion filter. If that has a slimy white/brown oil immulsion on it then there is moisture in the crankcase and water is leaking there some how. You can also dump your oil from the engine and let it settle to see if there is water in the bottom of the container when the oil is slowly poured off the top. Do this after the engine has ben cold overnight.

Hope that helps. I'm running about $500 to get this done and I'm doing the labor. Kinda painful where the two newest cars are down for repairs and the 84 diesel van still runs like a champ after 230,000 miles.

All the best,

SK