Disappearing coolant leak?

[alynch]

Originally Posted by Rob175

OK.....water pump has been replaced so the obvious leaks in front of the rear wheel on the passenger side are no longer........BUT......

I now have some very small coolant drops (at engine cool-down) appearing behind the rear passenger wheel with a few drops where the bumper cover screw is located (the one closest to the passenger rear tire). I pulled the truck lining up and the lining along with the truck floor is bone dry BUT THEN I realized that there is what looks like a "black masonite material" that creates a sub-floor which is raised up from the steel body. After removing the section of "sub-flooring closest to the coolant holding tank there is a very small amount of the newest bright yellow coolant that I soaked up with paper towels. I've NEVER had a leak under that portion of the car and there really wasn't very much....AND it was the yellow colored coolant my mechanic used to refill the system after he drained (the old coolant was more greenish)....so I know it's the new stuff used for the new water pump2 weeks ago.

I wiped the tank and the connecting hoses with paper towel and the towel was dry.....only the metal trunk floor had a little bit of coolant, which as I said, I dried up with paper towel.....

So here's my question, since I've never before had any sort of drops coming from the rear bumper cover area and know its the NEW yellow coolant added 2 weeks ago during the water pump install job (complete coolant flush and fill), and all sides of the tank and hoses are dry, could it just be a coincidence or could it somehow be related to the water pump install? (overfill, sloshing around in the tank, etc)......where does the tank overflow to?

Any thoughts?

Obviously, I plan on driving the car in the next day or two and then once again checking for any additional coolant in the trunk again.

Check the dimple in the middle of the underside of the coolant tank. That was where mine had a crack and the coolant was seeping out into the trunk. The coolant was then leaking around the rubber plug in the trunk floor eventually ending up in the same location you described above.