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It's been chilly here in Tucson the last week or so, but not freezing weather cold. It doesn't happen every morning, but twice this week I've had coolant on the driveway after starting the truck to let it warm up a bit. I haven't been using the block heater, because I didn't think it was cold enough, but what could be causing leaks that are intermittent? Thoughts?
theres this thing they call it thermal expansion or something like that. from what i gather stuff shrinks when its colder. the system creates pressure when it hot i think also. im no scientist by any stretch but thats how ive understand it
Need more/ better pics. I would clean it off and get it up to temp without driving it and get in there to see where it comes from when it first starts.
Need more/ better pics. I would clean it off and get it up to temp without driving it and get in there to see where it comes from when it first starts.
see that’s just it, this only happens when it’s “cold” (36-50 outside) and before reaching operating temp. It seems to be coming from that plastic t-fitting in the 1st pic, and it’s under pressure when it begins to leak as evidenced in the 2nd pic and spots on the driveway (not pictured). Only happened twice in 2-weeks. I ran the truck pretty much all day today and other than the first start, it’s been leak free.
Check the upper radiator hose where it mates to the radiator. Within the plastic coupler there is an O-ring. They start to go bad before the rest of the hose and are replaceable. You may see coolant dripping out of it when the engine is up to temp. If not visible, give the hose a slight squeeze and see what happens.
Similarly, there is an identical size O-ring at the coolant crossover pipe where the thermostat hosing sits. This is a 90 degree coupler. Why Ford can't just use ole reliable hose and clamp, I don't know.
I've had a similar experience with my 2019 6.2 CCLB. After 1.5 years without any leaks, I spotted some drops of fluorescent yellow coolant. Service advisor told me I had overfilled the reservoir, but I had not filled anything since it was at the full level from factory. Since my driveway is at a slight incline, I aways check fluid levels on level surfaces.
One day the level was a little under full so I filled it up. A few days later, the level was a little above. I checked the system for air bubbles, observed level cold and hot with heat on max.
Haven't observed any coolant on the driveway since.
Sounds like it heats up and seals off, not likely a split then and probably like deveroutdoors is talking about. Don't squirt yourself in the eyes squeezing, you'll find it.
Check the upper radiator hose where it mates to the radiator. Within the plastic coupler there is an O-ring. They start to go bad before the rest of the hose and are replaceable. You may see coolant dripping out of it when the engine is up to temp. If not visible, give the hose a slight squeeze and see what happens.
Similarly, there is an identical size O-ring at the coolant crossover pipe where the thermostat hosing sits. This is a 90 degree coupler. Why Ford can't just use ole reliable hose and clamp, I don't know.
BC3Z-8590-C
This was it! Perfect solution and came just in time. Thanks much!!
This was it! Perfect solution and came just in time. Thanks much!!
Glad to hear it. Just keep an eye on the fitting at the thermostat if you didn't replace that one. Probably best to replace these in pairs for $20 instead of a new hose for $150.
