2016 2500 6.4 hemi water pump

[zafo]

I live in NH. Two days ago, when the outside temp was really cold around 25-30 F, while driving, the engine temp went up and I had to stop. On the dashboard it showed 240F. When I looked under the truck, I saw the coolant leak. I pulled over, and put some coolant and drove home.
Today it is nice weather around 55 F, I wanted to check. The single OBD code in the reader was P2181, "cooling system performance".. Not much info. The problem doesn't show up at all. I ran the engine up to 210 F driving around and also revving up the engine on my driveway, the cooling fan always clicks in on time (meaning thermostat should be ok), never heats up above 210 F. The truck sounds and runs fine, no leakage under.
So what happened?? I am really scared to go for a long drive. Any ideas? Thanks

 

[Daw14]

When it leaked , did you observe from where ?
Water pump ? Over flow tank ?
Center of grill ? Or off to one side ?

You could look for water/rust stains on the lower portion of the water pump or elsewhere.
There is a weep hole on the lower part of water pump that leaks when it’s starting to go bad.

 

[zafo]

No, I couldn't observe much. It was nighttime and not much visible. But it seemed under the engine area (also looked at the stains today) not near the radiator, not overflow tank.
I had put maybe half a gallon of coolant, so it was serious leak.
I'll check the weep hole today if I can locate it.

 

[rzr6-4]

No, I couldn't observe much. It was nighttime and not much visible. But it seemed under the engine area (also looked at the stains today) not near the radiator, not overflow tank.
I had put maybe half a gallon of coolant, so it was serious leak.
I'll check the weep hole today if I can locate it.

I would suspect a slow-ish leak from your water pump. Mine would do the same thing, get super hot one day, so I'd let it cool a bit and add coolant. Once topped off I was fine for a couple weeks until it would do it again. Fix was a new water pump. Which checks out with you seeing the leak on the engine.

Assuming you replace the pump, ONLY buy OEM, aftermarket is trash.

 

[zafo]

Hi again. I am trying to drain some of the coolant, but I am not sure if this is the right bolt (see pictures). It is on the driver's side. But there is a notch on it so the socket won't fit. (What the heck, don't understand??) Do I have to use a hex tool for it? Thanks

 

[zafo]

Anyway, I was able to loosen it, see picture..(I didn't want to go further, because it is not turning easy anymore, I don't want to break or damage)
But nothing comes out of the pipe, not a single drop. Am I doing something wrong?
Maybe I should just forget the pipe, and remove one of the fasteners to drain the coolant?

 

[rzr6-4]

Anyway, I was able to loosen it, see picture..(I didn't want to go further, because it is not turning easy anymore, I don't want to break or damage)
But nothing comes out of the pipe, not a single drop. Am I doing something wrong?
Maybe I should just forget the pipe, and remove one of the fasteners to drain the coolant?

1) why are you trying to drain it? If you’re swapping the pump out, pull the upper and lower radiator hoses, heater hoses, and you will lose a little more as pull the pump itself off. No reason to use any drain bolts.

2) I’m not actually sure where that bolt is you are showing. Is that on the pump? Every water pump I’ve ever changed could’ve had that exact bolt, but like I said you don’t need to use it so that might just be why I don’t recognize it.

 

[tron67j]

That looks like the drain plug. Since nothing started trickling out as you turned it, could be the radiator has a bunch of gunk in the bottom and is clogging it. You might want to consider a full system flush, recommend removing the radiator and flushing that separate to not push gun through the entire system. Read up on it to decide what works best for you. Could start with running water into top of radiator and let it run out bottom hose connection tube. Make sure you fill with correct MOPAR coolant mixture only. Replace thermostat while doing all this.

Look with a flashlight all around your engine. The leak should be pretty clear once you spend a few minutes looking for the tell-tale drip line somewhere. Could be from the weep hole on the pump, connection point on the heater core, hose connections on the water pump.

 

[zafo]

1) why are you trying to drain it? If you’re swapping the pump out, pull the upper and lower radiator hoses, heater hoses, and you will lose a little more as pull the pump itself off. No reason to use any drain bolts.

2) I’m not actually sure where that bolt is you are showing. Is that on the pump? Every water pump I’ve ever changed could’ve had that exact bolt, but like I said you don’t need to use it so that might just be why I don’t recognize it.

I am not at the water pump yet, still investigating. I overfilled the reservoir because of previous panic, so I wanted to drain some out. But as tron67j said, it must be plugged, nothing coming out.
The bolt is on the radiator.

 

[zafo]

That looks like the drain plug. Since nothing started trickling out as you turned it, could be the radiator has a bunch of gunk in the bottom and is clogging it. You might want to consider a full system flush, recommend removing the radiator and flushing that separate to not push gun through the entire system. Read up on it to decide what works best for you. Could start with running water into top of radiator and let it run out bottom hose connection tube. Make sure you fill with correct MOPAR coolant mixture only. Replace thermostat while doing all this.

Look with a flashlight all around your engine. The leak should be pretty clear once you spend a few minutes looking for the tell-tale drip line somewhere. Could be from the weep hole on the pump, connection point on the heater core, hose connections on the water pump.

The leak has not appeared again, but the problem seems more serious. I went for a ride yesterday, and everything seemed fine. Today it was totally the opposite. The temps rose to 230 F in a few minutes,and I had to pull over. There was no leak at the bottom whatsoever. I checked the radiator hoses, both top and bottom was cold?? Obviously no circulation in the radiator. I waited a few minutes, opened the reservoir put more coolant since it looked mostly empty (I guess when engine gets too hot, it drains the coolant in the reservoir). I filled the coolant, but left the cap open. For some reason, don't know if a coincidence, but caused some change in radiator hoses. The top hose became very hot, the bottom one just warm. At least I was able to drive a few miles like that, because the heat didn't go over 230 F.
So, the important thing, top and bottom hoses being cold would mean thermostat problem?

 

[tron67j]

Top should be hot as it is return from engine, bottom should be cooler as it returns to engine. When an engine is cold the thermostat stays closed and no circulation occurs. When the engine heats up the thermostat will open and top hose will heat up as that is return from engine (your thermostat may be bad). If you have radiator cap off at start up (NEVER open a cap when engine is already hot) once the thermostat opens you can see the water flowing if pump is working correctly, but there could still be a restriction somewhere even when coolant flows. Rams are sensitive to type of coolant; sometimes it is purple but not always. Flushing system and installing correct type ( and new thermostat while doing that) and mixture of coolant could help.

 

[Wild one]

I am not at the water pump yet, still investigating. I overfilled the reservoir because of previous panic, so I wanted to drain some out. But as tron67j said, it must be plugged, nothing coming out.
The bolt is on the radiator.

That's the right "bolt" as you're calling it,it's the rads petcock.They can be a bit stubborn to turn out to where they let coolant come out the little pipe under it.Sometimes working it back and forth a couple times will help it turn out to where it'll drain,just don't wind it all the way out,as it can be a royal pain to reinstall.

 

[zafo]

Top should be hot as it is return from engine, bottom should be cooler as it returns to engine. When an engine is cold the thermostat stays closed and no circulation occurs. When the engine heats up the thermostat will open and top hose will heat up as that is return from engine (your thermostat may be bad). If you have radiator cap off at start up (NEVER open a cap when engine is already hot) once the thermostat opens you can see the water flowing if pump is working correctly, but there could still be a restriction somewhere even when coolant flows. Rams are sensitive to type of coolant; sometimes it is purple but not always. Flushing system and installing correct type ( and new thermostat while doing that) and mixture of coolant could help.

I removed the thermostat (it wasn't too bad by using a long arm socket, but the electrical connector was pain in the neck). 1) Is there any way to tell if the thermostat is broken before buying a new one? 2) Is it possible to short it by removing the thermostat from the housing and just use the housing for water flow? Thanks

 

[zafo]

Here is the picture of the hole where the thermostat resides. When I run the engine, isn't the hot coolant supposed to spit out here? I ran the engine about 10 seconds and no coolant came out of it?

 

[tron67j]

You may have a blockage, flushing will tell a lot. You can heat the thermostat up in water and see if it adjusts at the unit's operating temperature.

Hard to tell what is going on from typing, I recommend flushing and replacing thermostat to remove those as possible problems. Fill with correct type of coolant at recommended water/coolant volumes.

 

[Wild one]

Here is the picture of the hole where the thermostat resides. When I run the engine, isn't the hot coolant supposed to spit out here? I ran the engine about 10 seconds and no coolant came out of it?

If you've drained a fair bit of coolant as it looks like from the photo,there won't be any coolant coming out of the thermostat hole.

 

[crash68]

The single OBD code in the reader was P2181, "cooling system performance"

Is there any way to tell if the thermostat is broken before buying a new one?

That code can illuminate if the engine takes too long to warm up, most likely the thermostat is going bad.

 

[zafo]

If you've drained a fair bit of coolant as it looks like from the photo,there won't be any coolant coming out of the thermostat hole.

No. Actually I filled up the radiator from the top radiator hose, and it started pouring down from the thermostat hole in the picture. Doesn't this show that the coolant in the radiator going thru the whole engine all the way to the thermostat hole?
I will install a new thermostat tomorrow and see what happens..