Coolant leak

[Tuck91410]

2017 Ford Expedition limited… I have a coolant leak but can’t see where it is coming from. Don’t know what to do so I’m at the point where I’m just going to start replacing water pump and thermostat housing.. Any ideas would be greatly appreciated

 

[GaryH]

Just curious, but how do you know you have a coolant leak if you can't see a leak? I don't think its wise to just throwing parts at it. If the water pump or thermostat housing is leaking, it should be very obvious. Hopefully it's not an internal leak like a head gasket.

 

[Hamfisted]

Did you pressure test the system and look around with a bright flashlight ?

Coolant System Pressure Test Kit on Amazon




.

 

[glockmeister]

If you are low on coolent and do not see a leak, pull your oil dipstick and look at the level. Could be head gasket or cracked head and would not be a visible leak.

 

[99WhiteC5Coupe]

2017 Ford Expedition limited… I have a coolant leak but can’t see where it is coming from. Don’t know what to do so I’m at the point where I’m just going to start replacing water pump and thermostat housing.. Any ideas would be greatly appreciated

A common leak point is the water pump, which may only leak while the engine is running and the vehicle is being driven.

Based upon my experience and other posts on this forum, the original pump fails between 55,000 - 70,000 miles.

 

[Dennis_H]

Mine (2010 5.4) had a leak I could smell, but not find. It was crossover pipe so it would pool on top of block and evap off, or leak if enough angle. Think the 3.5 has same type of crossover.

 

[Motorcity muscle]

Check the lines to the heater, there's a tee that cracks, any misfire/ck engine light?

 

[JimmyC]

Clean the engine, dry throughly then wrap a paper towel around like leak points, drive for a couple of days, you’ll find it

 

[dkincaid32]

2017 Ford Expedition limited… I have a coolant leak but can’t see where it is coming from. Don’t know what to do so I’m at the point where I’m just going to start replacing water pump and thermostat housing.. Any ideas would be greatly appreciated

I'm surprised no one mentioned the turbos yet (super-common failure point). I have a 2017 as well, also with a coolant leak (maybe a pint every two weeks). Mine is leaking from the passenger side inboard turbo coolant fitting and there's moisture near the forward end of the crossover pipe. Its too hard to see without disassembly, but its either the thermostat housing or most likely, the forward O-ring on the crossover tube.

I'm amassing parts (got the infamous broken header bolt too) and awaiting on good weather to tackle them on a weekend.

 

[jonj13]

Check the hose connector at the bottom of the degas tank, they're a problem, the coolant line fittings on the turbos, also a common problem. My waterpump never showed any signs of leakage until the bearing failed and lost most of the coolant inside of a minute.