Coolant low by > 1 gallon

[adamsdaddy]

Good afternoon,

A couple weeks ago I posted about the loud fan running near 100% of the time and the interior fan not working. I suspected the thermostat but (over the phone) my mechanic said to check the coolant level and if it was low then it becomes a matter of finding the leak. Got back from an extended vacation and finally got around to checking the level and I couldn’t see any coolant at the bottom marker so I bought some orange Peak 50/50 stuff for $20. I kept pouring and pouring, stopping to make sure it wasn’t just clear and about to spill but nope. It consumed the entire gallon and barely reached the cold minimum marker.
I am less than excited at the prospect of a leak. It does have 80?something thousand miles so maybe a water pump though my mechanic said he hardly ever has to replace the water pumps. I would have noticed coolant on my driveway so I’m not sure where to start. I have (prior to adding coolant) been smelling hot coolant.

Anyone have a suggestion on where to look (known leak areas) ?

 

[Motorcity muscle]

Check back of intake heater hoses, leaks here usually cause misfires from coolant getting into spark plug wells. Have the system pressure tested or can do yourself if you purchase the tool. If you smell coolant it could be dripping on exhaust and burning off. If your getting smell by tail pipe that's a head gasket. Do not keep driving the truck you can hurt the engine. See you posted in third gen, what year is your truck?

 

[ManUpOrShutUp]

I had 2 heater hose failures around the 100k mark and opted to replace all 3 at the time. My water pump went around 165k or so I think. Advance Auto / Auto Zone have a pressure tester loaner tool. The one at Advance does not have a cap that fit my '11 out of the box, but after Dremel'ing just a hair off the tab on the one that was supposed to fit, it fit perfectly.

 

[99WhiteC5Coupe]

Good afternoon,

A couple weeks ago I posted about the loud fan running near 100% of the time and the interior fan not working. I suspected the thermostat but (over the phone) my mechanic said to check the coolant level and if it was low then it becomes a matter of finding the leak. Got back from an extended vacation and finally got around to checking the level and I couldn’t see any coolant at the bottom marker so I bought some orange Peak 50/50 stuff for $20. I kept pouring and pouring, stopping to make sure it wasn’t just clear and about to spill but nope. It consumed the entire gallon and barely reached the cold minimum marker.
I am less than excited at the prospect of a leak. It does have 80?something thousand miles so maybe a water pump though my mechanic said he hardly ever has to replace the water pumps. I would have noticed coolant on my driveway so I’m not sure where to start. I have (prior to adding coolant) been smelling hot coolant.

Anyone have a suggestion on where to look (known leak areas) ?

My 2015 Expedtion Limited 4x4 began losing coolant but I could see no leaks on the ground.

My Ford dealerllship pressure tested the system and said there were no leaks - and filled up the reservoir jug.

The coolant level continued to drop and I returned to the dealer and insisted they determine where the leak was.

The technician put the vehicle on a lift and saw that the water pump was leaking. He speculated it only leaked when pressurized while driving. The pump was replaced. That was at about 75,*** miles.

I also had a coolant leak prior to that (reservoir jug level dropping) - at about 55,*** miles, and the dealership determined the coolant reservoir jug was leaking (where the hose attached to the jug nipple - as it was cracked), and one heater hose was leaking. Both replaced.

Your 2016 has the same engine as mine - I’d check the water pump area for the leak, and examine all hose connections closely. My water pump did not leak with the engine off and the cooling system pressurized.

 

[adamsdaddy]

Thank you very much!

 

[John D]

I had a water pump replaced on my 2016, coolant was low and I noticed a gurgling sound behind the dash.

 

[Al Steel]

+1 on the pressurized leak. Coolant loss is either from the coolant being burnt or bled. If it's being bled and the leak isn't obvious (pouring out of some hose or cracked component) then you gotta go leak hunting... and bring a friend.

For Leaking, make sure the coolant reservoir is full to the cold mark, start and warm-up the engine to operating temp. Open ALL heater vents and crank up the heat so coolant is flowing through all the passages. Grab a flashlight and your friend. Have him/her rev the engine to between 2-3K while you start looking for leaks in the engine bay. Common spots are the water pump, filler neck, radiator hose connections, T-Stat housing, and firewall hoses/connections where the heater hoses enter the cabin. Some water pumps have a "weep hole" drilled into them. This small hole will begin to leak coolant when the water pump starts to go bad. Also look for "witness marks". If your engine bay is relatively clean your might see evidence of dried or damp coolant residue near the spot where the leak is occurring. If the leak is in the cabin it will be harder to spot, but if your footwells are damp or your HVAC is blowing damp/steamy air then that's a clue that your cabin radiator or lines are shot and leaking.

Burning coolant points to a larger issue like a blown headgasket, cracked head or engine block. This allows coolant to either mix with the oil (and vice versa) or get directly into the combustion chamber. Look for a white milky froth on the oil fill cap. A little is usually ok because of moisture during a cold start. A LOT of yellowish milky froth points to coolant in the oil.. that's bad. Also check your coolant reservoir for a black film around the fill line and black globs of oil in the coolant. Also bad. Lastly, if your exhaust looks like a steam locomotive and has a "sweet" smell to it, even on a hot day in the afternoon (cold days that is likely just condensation and water vapor) then that is coolant getting into the combustion chamber... again.. you get the idea. You can confirm bad headgasket, cracked block/head with leakdown and pressurization tests but that's a whole other level of technical.

Good hunting!

PS: The water pump, like any constantly rotating part (pulleys, alternator, A/C compressor), does go bad.. they don't last forever and RARELY last more than 150-200K miles. Kind of why most vehicle warranties typically expire just before that.

 

[Will Williams]

I notice that the heat was not coming out when the vehicle was idling. So I checked the coolant level. It was low. I filled it but at the time did not see any leak. To make a long story short , Today when I came out I saw a small puddle, passenger side near the passenger side door. And the level was aging low. I could not find any other places where any leaks. I have not jacked the vehicle up yet trying to get more info as to what to look for and options for repair. Mine is a 2007 whit 177,000 miles.

 

[Will Williams]

Has anyone ever used

Permanent Coolant Leak Repair with K-Seal​

for a coolant leak?

 

[Al Steel]

Where the puddle is may or may not tell you where the actual leak above is since coolant will sometimes "ride the rails", running along the frame and cross-members, and pool at the lowest point. But that could point to a heating system hose. I'd fill, run up to op temp, turn on the heat and check the hose connections near or at the firewall.