Coolant reservoir empty after road trip. Can't find any active leak but see coolant inside some plastic hose covers etc?

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SteveP

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This is really frustrating. 2003 Expedition. Noticed coolant reservoir a couple times , fill and it seems ok for a while. After a recent roadtrip noticed the coolant reservoir was nearly empty. I also noticed white residue sprayed over everything, almost like the fan was spraying coolant everywhere? If I run the car I don't hear any leaks or see any active leaks. But poking around and squeezing hoses etc I found coolant trapped inside of the plastic hose covers and other little places where liquids can collect. The 2 transmission cooler lines coming out the radiator had quite a bit of coolant in the plastic covers of those. So clearly there is some kind of intermittent leak going on but I can't find it when I look. Any ideas what could leak intermittently like this? I am scared to take this on anymore trips since i am worried it could go for real.
 

99WhiteC5Coupe

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This is really frustrating. 2003 Expedition. Noticed coolant reservoir a couple times , fill and it seems ok for a while. After a recent roadtrip noticed the coolant reservoir was nearly empty. I also noticed white residue sprayed over everything, almost like the fan was spraying coolant everywhere? If I run the car I don't hear any leaks or see any active leaks. But poking around and squeezing hoses etc I found coolant trapped inside of the plastic hose covers and other little places where liquids can collect. The 2 transmission cooler lines coming out the radiator had quite a bit of coolant in the plastic covers of those. So clearly there is some kind of intermittent leak going on but I can't find it when I look. Any ideas what could leak intermittently like this? I am scared to take this on anymore trips since i am worried it could go for real.



Sounds like a water pump seal leaking.
 

whtbronco

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My thought was also the water pump, but the weep hole which is oddly located on top. All 3 times I replaced my water pump it was because I found dry coolant that had run down the timing cover.

An extendable mirror can also help identify the source. The water pump is hard to see without a mirror and the weep hole is on the top driver side corner

If it is the pump I suggest a Motorcraft replacement and at $45 from RockAuto there's not much reason to try others. The hardest part of the job is getting the fan off the water pump.

 
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SteveP

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Sounds like a water pump seal leaking.
Ok thanks will check
My thought was also the water pump, but the weep hole which is oddly located on top. All 3 times I replaced my water pump it was because I found dry coolant that had run down the

An extendable mirror can also help identify the source. The water pump is hard to see without a mirror and the weep hole is on the top driver side corner

If it is the pump I suggest a Motorcraft replacement and at $45 from RockAuto there's not much reason to try others. The hardest part of the job is getting the fan off the water pump.

Ok cool thank you. I have a little inspection mirror I can try to use, will check. Dang just bought a bunch of other stuff from Rockauto.
 
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SteveP

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OK, so after removing the cover over the radiator I could not see any leaks but did see a white residue on a lot of areas. I went and borrowed a coolant pressure tester from Autozone, which was a pain because it didn't work on the resoirvoir, as it was made for radiators, it had some "universal adapters" that were big rubber corks basically, but they didn't work, they would just pop out when you started pumping the pump. So i had to go to a different Autozone to get some adapter to fit onto the resorvoir, I beleive this one here for anyone trying this later https://www.autozone.com/test-scan-...tools-radiator-and-cap-adapter-set/391377_0_0
. After getting the adapter and connecting everything, I started pumping the pump up and I could get it to about 6 PSI and notice the pressure drop. I could kind of hear a hissing from the top of the radiator part. Pumped it up again and when it got to about 6PSI, then I could see a line on the top of radiator get slightly wet and see some tiny bubbles coming out. Strange, kind of a hidden crack in the plastic that only appeared under pressure. Not sure whose bright idea it was to make a plastic radiator to try and hold pressurized boiling water, but then went back to Autozone to return the tools and get a new radiator. The guy at Autozone said yeah it makes sense that I didn't see a leak because the top of the radiator is basically all steam when the car is warmed up so it was just steam escaping from the top. I was able to swap the radiator and only had to replace about 4 gallons of coolant.
 
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