Odd Coolant Leak

[John03Z71]

I noticed this leak yesterday evening about an hour after I parked in my driveway. I went outside to take the garbage out and noticed a wet spot about 12" in diameter on the driveway almost perfectly centered under the engine. It was dark so I took a flashlight and noticed a coolant dripping constantly (a drop every 10 seconds or so) but couldn't get too good of a look last night to try to trace it. I crawled under and peeked up and it does seem to be trickling down from the water pump area, but I couldn't get a good view of anything that might be the source (up higher, weep hole, etc), just a trail of coolant. The vehicle sat overnight and when I came out this morning to get in (after sitting for 14 hours) the wet spot was still there, but not quite as large in diameter (maybe 6-8"), but I could tell there were still very fresh drips. Before I go tearing into it trying to track down the source, hopefully I can eliminate and narrow down a few things with this post. Will the water pump still leak after the engine is shut off? Mine was replaced about 5 years ago as an FYI. What else could be the possible culprit for constantly dripping even after the engine is shut off? I haven't gotten a low coolant level message yet but plan on picking up a few gallons of 50/50 today until I figure out the problem.

The 'T' connector on my heater core was leaking in the winter when I ran the heat, but the wet spot it created was in a different area on the ground. I haven't gotten around to replacing the 'T' connector yet. I also noticed I no longer have front heat. Not that I need it in July, but on a road trip this past weekend I tried adjusting my A/C temp up from 60 to 72-74 and noticed no difference, so I turned the compressor off and cranked it to 90 and let it run for a few minutes and it was just fresh air. Not sure if its related at all, just throwing it out there.

Thanks for any info.

 

[Nickn]

Could be the rear of the water pump or one of the two hoses that connect to the underside of the throttle body.

Water pump can leak with the engine shut off if the gaskets are bad and/or the rear panel is leaking but the leak would be more of a very slow trickle. There is an O-ring seal in the rear panel that can go bad causing the leak.

 

[SLCHOE]

Go rent a cooling system pressure tester from the parts store (usually free with a credit/debit card). Hook it up to the radiator fill and pump it up to 15-20 psi. Your leak and it's source will be VERY obvious at that point.

 

[Rivieraracing]

Just get a good flashlight, crawl under the truck and directly under the water pump, then move slightly in front of the water pump and look up and slightly towards the engine block and you will more than likely see a weep hole directly under the water pump at the pulley shaft and will more than likely see it still dripping. When they give out, it will do exactly what you are describing, not very hard to find it on your truck and see if it's leaking!

 

[John03Z71]

Finally crawled under with a flashlight last night, sure enough the weep hole is leaking. Thanks.

 

[Rivieraracing]

At least you know now, lucky for us replacing a water pump in our truck are way easier than other trucks! Hardest part is getting the clutch fan off of the water pump!