Engine overheats, coolant level drops

This morning my check engine light came on. As I was 4 hrs away from home, I couldn't check the OBD status and had to get going. After maybe 30 min driving, the truck stopped on an uphill in the 2nd speed and wouldn't turn on again. Then I noticed steam coming out of the coolant tank and inside it looked like the coolant was boiling pretty hard.

I rested the truck for about 45 min on the side of the road and refilled the coolant tank with water, as I didn't have any coolant. After I started the truck and went on the road, the engine overheated quickly after about 3/4 mi so I stopped again and got towed to a nearby town.

Once in town on a mechanic shop parking lot (it's Sunday so they're closed), I tried to diagnose if there are any leaks in the coolant piping system by letting the engine idle and I found that some liquid was leaking from an open ended rubber nipple (is this supposed to be hooked into something?) that comes out of the firewall on the passengers side (picture attached). Also the fat aluminum pipe that also comes out of the firewall, has a capped nozzle, and goes into the bottom of the engine block gets really cold and the underside of it collects and drips some liquid (picture also attached).

After that, we were able to drive it some 1/2 mi at 25 mph to a nearby motel without overheating but we're 180 mi away from home, where I would like to ideally get the truck to under some temporary fix so that I can work on the proper fix, if possible.

Any idea where the leak could be and if I may be able to make a temporary fix with supplies from a local Walmart to which I believe I can safely drive?

P.S.: I also noticed my serpentine belt was worn down to about half the width. Not likely to be causing a coolant leak but mentioning just in case.

 

first picture is the drain tube for your AC, (just water that drips out). Second picture, that is an AC line (any silver aluminum lines are AC lines), it will get cold and sometimes frost up normal. Third picture major problem, your belt has come off of the power steering pump and the edges are frayed. something has worn out and gave, I recommend taking it to a shop and have it check out.

*After looking again third picture, your belt on that pulley is half gone, shreded off.)

 

It's not actually off, it's just worn down to about half the width. But it's still turning.

 

the oil is at the second notch from the tip, looks alright brownish. I think that I may have not had the radiator cap on tight when I first drove off, which could explain. Also, when I took it off for the first time, it seemed like the gasket from the cap (white plastic ring) was loose and fell off into the pipe but I took it out with a screwdriver. Could that be causing it to steam off?

When the truck is idling, the engine doesn't overheat.

 

If the water pump isn't turning the engine will overheat very quickly. I had a fan belt break once going up a hill, I figured I'd fix it at the top. Temperature gauge was pegged in 15 seconds, it demanded attention now.

I'd replace the belt first and see if that fixes it. Most blown head gaskets are the result of overheating.

 

x2. I would change the belt imediately, chances are it isn't driving the water pump as well as it should so your coolant isn't flowing fast enough to cool off the engine. Belts are cheap, overheating your engine will rapidly increase wear.

 

The rad cap is designed to vent excess pressure. My guess is your coolant is moving too slow through the engine so it gets hot enough to boil, in which case your rad cap will vent the steam. Not necessarily a bad rad cap.

 

Is the water pump pumping the coolant through the engine?

 

yes. it circulates coolant through the engine and radiator. It takes the heat out of the engine and goes through the radiator to cool off. The water pump is the central pulley on the front of the engine, right above the crankshaft pulley.

 

That looks like the A/C refrigerant line and condensation dripping.

 

I went to Advance Auto, got a new belt, mounted it on, works fine, no overheating so far after a few miles. There is, however, a small radiator leak on the lower right (passenger side) corner of the radiator. I saw it when I took the skid plate off to pull the tensioner.

Thanks y'all for the feedback.

 

If you ignored the half worn away belt in the third photo. Already established that those are refrigerant lines and thus not the issue.

 

Unfortunately, it's overheating again after some 20 mi driving. The new serpentine belt works fine. It has to be something else.

 

I refilled the coolant tank with 50/50 and maybe after 20 mi it overheated again.

 

You can pressure test your cooling system, they sell kits to do it. Or have it done. It will help find the leaks too.

 

If the radiator is leaking, and you drive it on the highway, that trickle will turn into a big stream as it warms up and pressure rises. All the pressure inside caused by the water wanting to flash to steam instead turns to pressure that will empty the radiator. Doesn't have to be empty to cause a problem, just needs to air-lock the water pump. Also with a leak it is doubtful lost water will be replaced from the reservoir when it cools since air will leak in at the radiator leak rather than pulling water up and into the top.

Some questions come to mind.

Main one is what is the condition of the coolant? I had a friend once (ford taurus I think) that stopped by with overheating issues. Radiator fluid looked like coffee. flushed and filled with plain water to test, with thermostat removed, no water coming from the upper hose end. We took water pump off, and found that the vanes on the pump were completely gone. Normally they have an angle bent that is used to "sling" the water out. None on his. Replaced, refilled, and all was good. Ugly coolant is not just something bad to look at, it heralds other problems.

I assume when you added water you refilled the radiator and not the reservoir? Believe it or not I know someone who shall remain nameless to protect the guilty, that had a major overheating episode. Told them to add water and we'd check the next day (this was late at night when nothing parts-wise was open). Called me back and said it was overheating again and they had no water. Drove about 15 miles with a 5 gallon can of water. When I took the rad cap off and poured water in he asked "what are you doing? Water goes in over HERE. (pointing to the reservoir)." I asked "how in the hell is it going to pull the water in from that, do you think there is a rat in the radiator with a LONG straw or something?" To make it short, once we got the trapped air out and antifreeze in, all worked well (his had a couple of bleeder points on a couple of high-point water hoses that could trap air.).

Once you replace rad, which is not a hard job, you still have to take your time to get most of the trapped air out. Air will eventually dissolve in the anti-freeze solution, but not very quickly. Get a big bubble of air and it can air-lock the water pump and it will overheat quickly. The service manual gives hints, but the main problem is always the upper radiator hose. Air is less dense than water and always seeks the highest point. That is often a hump in the upper (return) radiator hose. Ideally you end up with nothing but liquid in there.

 

I was putting water and later coolant in the tank that was open here in this picture. Should I have done it through the other cap to the left?

 

Check your oil and look for a milkshake on the dip stick.

Does it overheat sitting at idle?

 

I am aware that the refrigerant lines are not the issue.

 

Here is the dipstick