Hi Gang,

2008 4.0 Mustang. 79,000 miles (freeway).

I checked previous posts... have some pointers... but a different scenario.

Couple weeks back posted an inquiry about my water pump. I woke one morning to a small puddle... 3" x 3". It was coolant (color and taste). Thought I'd have to replace the water pump. Check it the next day... the next day... throughout the days... nothing. No leaks. All seemed good.

Last night drove the car (80 mile RT). This morning woke up to a little river of coolant. Jacked up the car and could not identify from where the leak was coming. Drove to the store for some coolant... added about half gallon (which is the same amount I added last time). Drove it home (5 mile RT). Parked. Have been checking it hourly... no leak. Got under the car with a flashlight... car running... nothing.

It's not overheating. Engine is running fine. No signs of leaking.

What I'm looking for is some guidance on how I may troubleshoot this. Is there something I should be looking for (other than the obvious)? I've perused the threads on this forum and there are a lot of sharp minds.

I'm hoping one of them can help me.

Thank you.

 

Check the weep hole in the water pump for signs of leakage. It sounds like the internals of the water pump could be starting to fail and only show signs after prolonged use. Seeing its an 08, do you still have a warranty on it?

 

Ahhh... Mr Penguin.

The only warranty left is the powertrain (good up to 100,000 miles). I'll call the dealer today and inquire.

Thanks! I had not thought of that. Powertrain I was thinking if the engine was damaged.

 

Well it normally is, but they may at least be able to cover troubleshooting or they may find a bigger issue than whats thought. I believe the powertrain includes the engine

 

Yup.

You might also want to pop the hood and check around for any obvious signs of coolant. It could be that the leak only happens when the engine gets hot enough and starts building up pressure in the entire system (thermostat opens etc). Radiator caps are notorious for this kind of thing when not tightened down all the way, or when they are starting to fail.