My truck overheated and blew off the lower hose? Wonder what damage there was.

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Always an adventure. Got the F350 back together. I put about 50 miles on it since I replaced the passenger side head gasket. No issues that I could see. Wasn't using any coolant in those 50 miles / numerous heat cycles, had way better power than before.

I thought I did a good job bleeding it, but maybe not? The upper hose was getting rock hard. Not instantly, but once the engine got warm, it would get rock hard. To the point I was afraid to touch it and it would explode. I did notice there was coolant misting out of the upper hose at the thermostat housing onto the hood but not a lot of pressure coming out of the pressurized bottle when opening the cap. I tightened up the upper hose and continued on with my day. There was normal modular engine condensation on the oil cap. No overheat reported via the OBDII scanner - the gauge on these runs off of the coolant crossover which could get an air bubble and not report. The OBDII reports from the sensor in the driver's side head.

Had to go about 25 miles to retrieve my Jeep and tow it home. Was keeping an eye on the temp gauge and it was doing good. Almost there, the lower hose burst off. I looked down and saw that it was pegged out and then went into 4 cylinder "failsafe" mode. Pulled over. Looked around and saw that the lower hose was off.

Initially I thought the hose was lose, but I had to back off the clamp a ton to get it back on. That makes me thing that it made a massive amount of pressure and blew the lower hose off.

I also noticed that nothing was not. The coolant that was still dripping out of the lower hose coming from the engine was luke warm. Ambient temperature was 20 degrees, but I've had overheated engines before - everything feels warm.

Unfortunately, there was a plow behind me that had to get through so I dumped a gallon of coolant in .. which did nothing. Took off, overheated, shut off and costed. Did that 2 or 3 times until I got where I was going. Ended up coming in too hot to a driveway and put it in the ditch with the trailer.

At this point, I was just done with the whole thing. Nothing felt not. Oil didn't taste sweet, nor did the condensation on the oil cap. Found a Spigot, put 4 gallons of straight water in.

Then to get it out of the ditch I figured I was going to send some parts flying. That poor 5.4 saw the rev limiter for a bit trying to get out of the ditch. But it got out.

Loaded up the jeep and headed back. I was not nice to it. I was just done with the thing. I ran that engine harder than it's been run before. Foot to the floor as much as possible. Every shift at the rev limiter.

The weird thing was - no overheat. Temperature via OBDII didn't get above 200. In fact coming up the hill to my house I stopped right at the top and grabbed the upper radiator hose and it felt normal. Some pressure but not rock hard. No coolant bubbling. Oil was clean. No condensation or milkshake on the oil cap. It also stopped misting out of the upper hose.

So is it possible it was air locked bad enough that it would blow the lower hose off? I've heard of it happening before but don't quite understand how it works. Also hoping I didn't damage anything but a few momentary overheating events on such a cold day. Nothing felt warm.
 
I would try to vacuum fill it if possible, if not use a bleeding funnel on the degas bottle.

Did the upper hose get hot when the engine was up to temp? If so you had coolant flow.

I would try to get it all back together and see if you can T in a gauge on the system and drive it to watch for cooling system pressure spikes or overpressurization while driving it.

Did you have proper heat out of the vents?
 
That sure sounds weird. It sounds more like a blockage of some sort. With that system being open to all parts of the engine, EVERYTHING should have been pressurized. Are you sure all of the passages in the head gasket matched the openings in the block and head?
Thermostat in correctly?
 
Did you check the coolant level after the first few trips?
My best guess:
Either the head gasket replacement failed, or the previous head gasket failure damaged the hose and you didn't replace it.
 
OK. Not sure about other people, but after getting back on the road from an overheating event, I usually drive as gently as possible.

Usually I'm the same. I was very mad at the truck at that point. If it gave me any more trouble, I would have left it on the side of the road with the title signed , called the scrap yard and towed the trailer home with the unregistered Jeep. I was that done with it.
 
Did you check the coolant level after the first few trips?
My best guess:
Either the head gasket replacement failed, or the previous head gasket failure damaged the hose and you didn't replace it.

Everything was good before. I did compare the two head gaskets and they are the same. I had some confusion as to whether or not Romeo / Windsor modulars used the same gasket so I checked closely.

The previous head gasket failure was an oil passage that corroded and leaked out of the head gasket externally
 
It's not how long he ran it, but how hard he beat on it, that counts.
I did this once on a Ranger with the 2.9. Saw a cloud of steam from the front of the car and then limped it home for 2 miles very gently. Worked fine after that, bottom hose too.
 
No pressure in the bottle tells me that the line(s) feeding it were not allowing pressure through to be burped out of the pressure cap. My other thought is the hoses are done and were weakened from age and heat.
 
Sorry for your misfortune after hard work.For sure toss those two clamps as a possible problem,then oil and filter change with an oil analysis thru Polaris Labs.That might confirm no problems, if it comes back bearing material,then you'll have time to think of your next move.Good luck
 
Usually I'm the same. I was very mad at the truck at that point. If it gave me any more trouble, I would have left it on the side of the road with the title signed , called the scrap yard and towed the trailer home with the unregistered Jeep. I was that done with it.
I get being at wits end with things, but you need to settle a bit. Rev limiter to get out of a ditch? Careless driving putting it into a ditch? Slamming on it worse with a trailer and vehicle in tow when the whole thing was questionable? Really?

Sounds to me like you tightened the hose too much, and either cut through the hose or squeezed it out.
 
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Ah dang it, I jinxed you. If it's any condolence, my friend's Wrangler is still very broken. 🤣

My previous Explorer blew apart one of the radiator tanks from some sort of cooling system situation. I "fixed" it with K-Seal and a new radiator because I wanted to try something before a whole head gasket job. Actually worked great. K-Seal only works on combustion/air to coolant leaks, but that may be what you have going on given the pressure. Worth a shot where you're at with this truck.
 
I get being at wits end with things, but you need to settle a bit. Rev limiter to get out of a ditch? Careless driving putting it into a ditch? Slamming on it worse with a trailer and vehicle in tow when the whole thing was questionable? Really?

Sounds to me like you tightened the hose too much, and either cut through the hose or squeezed it out.
As long as you aren't putting other people in danger and the vehicle is ultimately your responsibility, sometimes you just can't baby the thing anymore and have to wind it out. But as someone who has floored an Isuzu NPR with the oil light on (not low, the used engine was just already really well worn when it was installed) in the last few days I may not be the best judge of this. I treated the NPR to a bottle of Lucas the next day.
 
So the water from the radiator was only warm yet the temperature of the engine was hot enough to blow the lower hose off which would be 260 degrees or so. This would indicate insufficient flow due to possibly to low coolant or a gas bubble in the system. You were lucky the weakest link was the hose and not the cabin heater core. Is the problem resolved after refilling?
 
I get being at wits end with things, but you need to settle a bit. Rev limiter to get out of a ditch? Careless driving putting it into a ditch? Slamming on it worse with a trailer and vehicle in tow when the whole thing was questionable? Really?

Sounds to me like you tightened the hose too much, and either cut through the hose or squeezed it out.

It was rural Oswego county , the road sees 3 cars a day. Unfortunately there was a VERY impatient plow driver behind us. It was a friend's driveway so not a random driveway I was blocking. But I was coasting with no power and in an area with no cell service. Not really able to call for a tow or anything in that situation. Wheel speed works wonders sometimes ;)

And it's a triton v8. Towing 6000 pounds it's about as fast as your average Vespa in the hills :ROFLMAO: The difference is , instead of going up the hills at the usual 25, I was going a whopping 38!


So the water from the radiator was only warm yet the temperature of the engine was hot enough to blow the lower hose off which would be 260 degrees or so. This would indicate insufficient flow due to possibly to low coolant or a gas bubble in the system. You were lucky the weakest link was the hose and not the cabin heater core. Is the problem resolved after refilling?
It was fine on the way home with more load. I'm really thinking it was a gas bubble preventing flow. Heater works great still and doesn't leak. Of course, these are relatively easy to change, so I'll never need to change it.
 
It's weird that the gas didn't burp through your rad cap. Might want to test that or just replace it.

You can make lots of pressure without overheating if your cap is bad.

An air bubble in a rad hose can feel harder than water, it's just how we as humans perceive our world.

I was concerned you put the head gasket in backwards/ upside down, blocking a coolant passage, but you looked it over real good. IIRC GM 4.3s used to have an issue with this.

Sometimes you have to rev things with the front end pointed to the sky to burp air. Usually the heater core will give a nice waterfall sound when this happens.

I don't know that Ford has a Northstar-style 4 cyl failsafe mode. This doesn't sound good at all.

Used medium duty trucks aren't cheap. Go smoke a bone, kick some stumps out back, and reevaluate.
 
Sometimes you have to rev things with the front end pointed to the sky to burp air. Usually the heater core will give a nice waterfall sound when this happens.

I don't know that Ford has a Northstar-style 4 cyl failsafe mode. This doesn't sound good at all.

Ha! Funny you should mention that. When I filled it up in the ditch and started it, I thought the heater core blew out because I heard a a whoosh and running water in the heater core for a second. It was definitely nose up.

I don't know the criteria, but according to the owner's manual - when an overheat is present , it will alternate pairs of 4 cylinders. When it gets really hot, it will shut the engine off completely.

Insurance on medium duty trucks can be a bit on the high side and I'd want something pre-emissions if it's a diesel. But 6.0L gas powered Isuzus do get a second look on FB Marketplace and CL. Possibly E-350s but apparently 4.6 and 5.4L powered van/wagons have the same 4R70/5 transmission as my grand marquis or a F-150. Not sure how I feel about that trans for my use. However, friends of mine who are mechanics rarely if ever do transmissions in E-series vans but apparently frequently in the GM vans.
 
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