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1999 Dodge Intrepid Repair Question


Topics covered: Water pump, Coolant, Cooling system.
Mileage: 118,000 miles.

Asked on April 5, 2011

Water leak

My 99 intrepid has a water leak. Had pressure test run. Did not leak. Started again after return home. Could it be hose, clamps or freeze plug/ Leaking underneath.
Avatar Asked by Bethany1

Answer

Replied on April 5, 2011

Is it water or coolant? Where is it leaking, inside on the passenger side floor or on the ground? By "started again" do you mean it was leaking as soon as you got out of the car or after it sat for a while and cooled down?

Tiny Answered by caradiodoc (expert)
17,280 answers provided
Replied on April 6, 2011

It was water. It is leaking on the bottom of the engine at the front. When it cooled off, it started leaking. The pressure test showed no problem with the radiator or the water pump.

Tiny Response from Bethany1
5 questions asked
Replied on April 6, 2011

There's some confusion. If you had the cooling system tested it should be leaking coolant, not water, unless you only have water in the cooling system. If that's the case, water doesn't have the same seal conditioners and water pump lubricant that is in antifreeze. That alone could lead to a leak. If it is indeed the cooling system that's leaking and it's near the front of the engine, the water pump is the most likely suspect, especially given that it leaks when it cools down. The lip seal around the shaft will balloon up and seal better when pressure builds up in the system. It will relax and open up and leak when there's no pressure.

Tiny Answered by caradiodoc (expert)
17,280 answers provided

Replied on April 7, 2011

I believe the coolant is so weak that it is mostly water. It goes from leaking a lot to no leaking when cooled down. Do you think adding coolant would rectify the problem if it isn't the water pump?

Tiny Response from Bethany1
5 questions asked
Replied on April 7, 2011

No. The seal conditioner additives in antifreeze will keep seals in good condition but it won't fix those that are already leaking. First you said it leaked a lot when it cooled off, now you're saying there's no leak when it cools down. It could be the level is down below the point of the leak at times so no additional leak will show up, and it's possible for a seal to stop leaking when it's warm because pressure that builds up in the system holds the seal against its sealing surface. I'm still inclined to suspect the water pump. One thing you can do is to fill the coolant, (water is okay at this point), then drive the car far enough to warm it up. Disassemble the front of the engine to get to the water pump, then inspect the area with a black light. The dye will show up as a bright yellow stain that you can follow up to the source of the leak.

Once the leak is solved, install a 50/50 mix of antifreeze and water. The antifreeze contains corrosion inhibitors, seal conditioners, and water pump lubricant. Those additives wear out over about a two-year period which is why replacing the antifreeze is a part of normal maintenance.

Tiny Answered by caradiodoc (expert)
17,280 answers provided
Replied on April 11, 2011

When the car was leaking the water was full. I was told the water pump would leak constantly. So many opinions but now all I am is confused.

Tiny Response from Bethany1
5 questions asked

Replied on April 11, 2011

After rereading my previous reply, I have to clarify that you can add a bottle of dark purple dye to the cooling system, THEN drive it a while, then check for bright yellow stains with a black light.

A water pump does normally leak all the time, but it is also common for some to not leak when the engine is warm. It depends on how it fails. If the rubber lip seal wears out, it can expand and seal when warm or when the normal pressure buildup pushes the seal against the spinning shaft. Seal failure is most common when running just water in the system. Antifreeze contains seal conditioners, water pump lubricant, and corrosion preventers.

If the bearings wear out they will let the water pump's shaft wobble and move away from the lip seal. The drive belt holds the shaft off-center so it will leak all the time. Nothing will solve that except replacement of the pump.

Tiny Answered by caradiodoc (expert)
17,280 answers provided
Replied on April 12, 2011

Thank you for the info. I am taking it to a mechanic this week.Your input ha been helpful

Tiny Response from Bethany1
5 questions asked