My 93-190E had a problem with the radiator/coolant and I hope somebody can give me good advice.

4 months ago, I found my 190E coolant is losing very quickly. The service guy told me the water pump was not working and he replaced it. It worked well until a few days ago, the problem reappeared. This time the problem seems more obvious. After the engine stop running for a few minutes, I can see the coolant drips away from the bottom of the car (I couldn't locate where it is leaking) like it is running from a tap!

What could be the reason for this? Rusty radiator inside? The problem doesn't seem to happen when the engine is running. Really hope to get some expert advice.

Thanks

Well with the engine running and no leaks, it sounds like the cap is not holding and the overflow is not getting back to the expansion tank. On the top of the expansion tank, where the cap is secured, below the cap there is an overflow hose attached to the neck. Trace that to the other end and see wheree it terminates. You will probably need a new cap. With the engine of and hot, the pressure in the cooling system will rise temporarily and this could be the trouble.

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Jeff Lawrence
1989 300e
2000 Dodge Grand Caravan SE
No matter what you fix, there will always be something else to fix..
"Warranty" is just another way of postponing the inevitable.

Let the engine cool down and trace where the coolant is coming from. You pretty easily identify it from a trail of what looks like white scale. The coolant looks that way when, it starts drying. You might also want to put a paper towel under the car after driving. This may help identifying where exactly it is coming from. Otherwise, bring the car back to where you got it fixed. It could be anything. Check all hoses, coolant resevoir, heater hoses, and the weep hole of the water pump. Where exactly is it leaking? Is it in front of the engine or middle of the car? If it is in the middle of the car then, it is probably coming from the overflow tube due, to the radiator cap being faulty.

Thanks for both of your advice.

Actually I also suspected it was the reservoir cap, but then I found that it was not likely. The first day I found the problem again I noticed a strange sound. I heard some 'seeeee....' sound coming out (again I could not locate it exactly, sorry) I suspected it was the cap and the overflow hose, but the overflow tube is not dripping.

For the overflow hose, should it be connected for both ends? I found one end of the hose is connecting to the neck of the reservoir just below the cap, but the other end is not connecting anywhere. Do you know where should it connects to?

The coolant seems to drip from somewhere near the engine. The first time I found the problem I found there were 2 places dripping! One seems to be near the water reservoir, and one seems to be at the front of the engine. But the second time it seems only dripping from the front of the engine.

Thanks

There are a number of places that coolant can leak from. The radiator itself, upper and lower hoses, heater bypass hose and so on..I am afraid you will have to really look very closely and try to determine the source. Do you have the 4 cyl or the 6 cyl engine?

__________________
Jeff Lawrence
1989 300e
2000 Dodge Grand Caravan SE
No matter what you fix, there will always be something else to fix..
"Warranty" is just another way of postponing the inevitable.

I don't know if this applies but I have a '88 260e that does the same thing. I investigated it today and found the water pump leaking at the base where it mounts to the engine. It was hard to track down because the water runs down the engine and along the oil pan and drips out over that plastic shield. I hope this helps..

my 190e2.6 leaks coolant after a stop at the rear of the engine. I've traced this to the heater area, where some coolant is run through.

when the engine is stopped, the coolant circulation stops and the coolant temperature and pressure slightly increase because of the residual engine heat. This increase in pressure makes the coolant leak from a loose hose fitting somewhere in that heat exchanger.

sometime i will open up that part, tighten up that loose fitting, and oil my noisy fan as well ... in the meantime, i just check the water level periodically.

Steve,
Do you still have the old plastic thermostat cover?
Check it out.

Clauser1

One more thing to check: The bottom side of the water pump has a hole which leaks when the pump fails. You can not see this hile from above, but when you take out the pump you will see it. Mine was leaking from this hole and I had to change the pump. Just one more thing to check...

Check the heater control valve. Leaks under the passenger side of the car.

I had the water pump replaced on my 300E by the dealer about a month ago, after discovering the leak at that component. Drove it home that evening and discovered the same amount of leakage the next morning! Turned out that they did not torque down the water pump the first time.

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