07 Expedition coolant leak

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Jacob Garff

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I've got an 07 expedition with a coolant leak, that I can't find. When I pop the hood open, I don't see anything wet anywhere. Behind the passenger wheel, there is a puddle. Some drips off of the metal, the rest drips off of the plastic molding in the wheel well. A few weeks ago, turned on the defrost and could smell coolant, but the reservoir still showed that it was full. It has been parked for the last couple days, and there was a good sized puddle under it today when I got home, checked the reservoir, and it is now low. Any ideas?

Could this be my heater core?
If so, how big of a job is it?

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outdare

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If your not loosing any coolant I would try a vent cleaner of some kind. Not sure I jump to the heater core yet. I would check the hoses again. Also look under the hoses on top of the engine since I had replace mine do to a leak.

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ExpeditionAndy

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Check the tees in the engine compartment, you could have a small crack that opens under pressure and allows coolant to follow the hoses down and drip by the wheel. They have been known to crack with age.

If you had a leak in the core, I would expect to see some evidence in the passenger side carpet unless it is leaking into the evaporator box and coming out the condensate drain.
 

bobmbx

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Wipe the inside of the windshield with a dry white paper towel. If you see a residue the color of your coolant, its your heater core.

But since you said you see drips on the ground, its most likely a hose in the engine compartment. Just follow the wetness "uphill".
 

1955moose

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Jacob, as any decent mechanic will tell you, borrow a coolant pressure checker. You should be able to borrow one from auto zone or oreillys. Most smaller leaks only show under pressure. You pressure it to cap pressure, and walk vehicle, looking for leaks. Let us know what you find.

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Jacob Garff

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Jacob, as any decent mechanic will tell you, borrow a coolant pressure checker. You should be able to borrow one from auto zone or oreillys. Most smaller leaks only show under pressure. You pressure it to cap pressure, and walk vehicle, looking for leaks. Let us know what you find.

Sent from my N9131 using Tapatalk


I went to O'Reilly yesterday, didn't get the tool since it's over $200 to rent it. Yes, I know that you get the money neu back when returned, but didn't do for various reasons (primary being that in a full time student and font exactly have the extra money right now).
I checked it last night and it had stopped. Today, ad of a few minutes ago it's a steady drip again. Opened up the cab, swear I smelled coolant again.
Traced the last news, can't find it external anywhere. Almost 100% sure it's the heater core.

How big of a job is it to fix it myself. Honestly, time and money are both issues, d/t being in school. Are there any special tools in supposed to have? All the tutorials I can find are on F150's from early 2000's or late 90's.
 

1955moose

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Jacob, you can probably have a small mechanic shop do the pressure test for a small amount. As far as replacing the heater core, their not easy, but do able. If it is the core, I would read up on removal and replacement, as well as pick up a repair cd online. Get a dealer one, the aftermarket books like Haynes, or clymers, aren't worth buying, as they cover too many vehicles. Doing most heater core jobs is at least an 8-11 hour job. Let us know what you find.

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Jacob Garff

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Jacob, you can probably have a small mechanic shop do the pressure test for a small amount. As far as replacing the heater core, their not easy, but do able. If it is the core, I would read up on removal and replacement, as well as pick up a repair cd online. Get a dealer one, the aftermarket books like Haynes, or clymers, aren't worth buying, as they cover too many vehicles. Doing most heater core jobs is at least an 8-11 hour job. Let us know what you find.

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Which company do you suggest getting the manual from? I'm looking at Factory Manuals, year specific (https://www.factory-manuals.com/exp...2010-2011-2012-factory-repair-manual-237.html).
I'm just wanting to make sure I get a good one.
 
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Jacob Garff

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I just went back outside and rechecked it. I washed it last night and backed it into the garage. The plastic mounding is now dry, and it is dripping off of the bolt that holds the body to the frame. I can trace it up to a seam where the firewall comes down. Open the door, and it smells like antifreeze. And it's dripping pretty good. Again, haven't driven it since Wednesday, it just keeps dripping away.
 
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