Sprung a coolant leak

[Eidolon]

So my G8 GXP appears to be leaking coolant from an attach point at the engine. It's completely stock, and while it's been cold around here in NC, the coldest it's gotten has been in the 20's and 9 nights out of 10, it's garaged. I'm about to head to Advance Auto Parts to fill the thing with coolant, then hope I can make it to the dealership.

Picture of the spot under the engine where the coolant seems to be leaking:
http://eidolways.com/images/G8/leaking/engine.jpg

Picture of the cradle under the car from whence the coolant is dripping:
http://eidolways.com/images/G8/leaking/cradle.jpg

So it's either the hose, the connection point or, heaven forbid, the coolant pump. Thankfully the thing's under warranty. Still, this would be the first serious issue it's had, and at only 17,000 miles.

[BigV8]

Hopefully nothing to bad, but then again you have the warranty. Good luck.

[WickedMom]

Probably a water pump... no worries. If it is, there are two designs.. both take the same amount of time to do and are easier to do than a Yukon Denali with a 6.0 in it. Piece of cake, IMO.

[Eidolon]

Well, however much the car has leaked, it isn't enough to cause it to overheat. I drove it to Advance Auto with the heat on. Of course, that wouldn't help if the engine had no coolant. But the heat worked fine and the coolant stayed between 87 and 92 C the entire time.

Made it to Advance Auto Parts, bought some Prestone Dexcool 50/50, put some in the car (looked like it still had 2/5 in the reservoir), spilled a good bit, hope the dealership doesn't think my spill is the leak I'm describing.

Note to self, clean that off later with a little water.

<SIDE NOTE>
Can you spray off the engine compartment of this car with a hose?
</SIDE NOTE>

Made it to the dealership just fine, this time with the heat off, car still didn't overheat.

They should get a chance to look at it tomorrow. Here's hoping it's nothing big. If it's a problem with the engine, then the parts should be more readily available from the Chevy dealership next door, which is good.

So in all, it's odd that the car lost enough coolant to create a rivulet on the garage floor, yet by all appearances it still runs just fine.

[WickedMom]

Yes to your side note. I suggest to use low pressure, avoid the fuse block area. Also, if the engine is not stone cold, leave it running and stop if there is ANY change in it.

[Eidolon]

You were correct, the water pump had gone. Replaced under warranty. And thanks for the tip about the washing!

In other news, I dropped by Advance Auto Parts and purchased some Prestone-brand 50/50 "GM Dexcool approved" coolant to top it off. While they may have flushed the system to replace the pump, so it may be a moot point, any foreseeable issue with mixing this fluid and the stock fluid?

[69project]

No, if it is approved fluid you should be fine.

[99-LS1-SS]

You were correct, the water pump had gone. Replaced under warranty. And thanks for the tip about the washing!

In other news, I dropped by Advance Auto Parts and purchased some Prestone-brand 50/50 "GM Dexcool approved" coolant to top it off. While they may have flushed the system to replace the pump, so it may be a moot point, any foreseeable issue with mixing this fluid and the stock fluid?

Could you smell coolant? I keep getting a faint coolant smell from my car. I'm overly sensitive to the smell of antifreeze though.

[Eidolon]

Could you smell coolant? I keep getting a faint coolant smell from my car. I'm overly sensitive to the smell of antifreeze though.

I could once I was outside the car, as the leak was not that bad. It was a fair amount of fluid, but not enough to seriously drain the system or keep it from working. Mind, I do still smell some coolant even now. I'm guessing there's still some in the engine compartment that will burn off/evaporate over time.

The place it ended up leaking from, according to the dealership docs, was the WEAP hole on the water pump. This is apparently an overflow drainage hole such that internal failures of the pump have someplace to relieve the pressure. According to a coworker, this kind of drainage would by caused by a failed shaft seal (I'm guessing the input shaft, driven by the belt). That would explain why the pump was only leaking and not locking up and taking my serpentine with it!

[GPDAN]

thats good that it only was the water pump, early 09 i had to replace the whole radiator and had to wait 2 weeks for it to come in stock.

[El.Diablos.G8]

You have me checking mine