Coolant overflow leaking fluid after truck shuts off

[Bulldogtt]

Good day to all my son has a 2015 ram 2500 power wagon. Noticed fluid leaking from overflow tube after driving. So for a few days now he has been monitoring it. After driving for a while when he shut her off the overflow bottle immediately fills up then overflows. All is normal when driving but the odd time the temp jumps 5 to 10 degrees but it does this intermittently. there seems to be no pressure in hoses to rad at times either. My question is what could cause the back purge when turning truck off. I assume the t stat could be stuck not functioning properly. Is it possible that the cooling system has an air lock somewhere. If it was air lock what would get the air out. Just not sure off direction to go. Info on truck. 3 years ago the hemi ate a couple of rollers and the engine was redone. It had a new water pump installed. New thermostat installed. Complete new coolant replaced. coolant system parts were hose flushed while engine was removed. Any suggestions would be helpful. I am leaning towards thermostat but not 100% sure.

 

[04fxdwgi]

Is the radiator cap good? Test cap and the cooling system ability to hold pressure.

 

[crash68]

As he said ^^^ check the cooling system pressure cap. The 6.4 uses a degas bottle so the risk of air being trapped in the engine is lower.
Also check the coolant for combustion byproducts, there is tests that determines is exhaust gasses are entering the cooling system, that could be from the head gaskets, EGR cooler, or possibly a cracked head/block.

 

[Bulldogtt]

Thanks for the replies it is well appreciated. The story unfortunately gets twisted As I get updated info. So I now have found out that he is only putting water in the cooling system to replace lost fluid and he has no idea how much or for how long. Yes he’s an idiot.
Is it possible that the bottle cap pressure is releasing is due to higher pressure due to I’m assuming a mostly water mix? This mostly water mix could also trap air easier to I’m assuming. Is it possible that the thermostat isn’t opening due to an air lock by the housing or am I reading way to far into it.
Yes I have told him he needs to drain system completely, then flush it and then add the correct fluid and correct mixture if needed.
Anyways thanks again for response

 

[crash68]

So I now have found out that he is only putting water in the cooling system to replace lost fluid and he has no idea how much or for how long.

If he decides to buy the coolant in concentrated form to use either distilled or de-ionized water to mix the coolant with.

 

[GTyankee]

I have to wonder if he is over filling the coolant recovery tank

 

[CanuckRam1313]

Sage advice above!!

I'd caveat this all by adding that he should consider doing a full coolant flush & fill with only MOPAR 50/50 mix, and maybe a new OEM t-stat and rad cap, too! (or MOPAR concentrated and then mixing the ratios properly with the correct mix add-in )

 

[nlambert182]

As he said ^^^ check the cooling system pressure cap. The 6.4 uses a degas bottle so the risk of air being trapped in the engine is lower.
Also check the coolant for combustion byproducts, there is tests that determines is exhaust gasses are entering the cooling system, that could be from the head gaskets, EGR cooler, or possibly a cracked head/block.

I hate to say it, but I had this happen on a Powerstroke... I chased my tail until doing that test. I had a case of blown headgaskets.

 

[GTyankee]

Like the liquid soap advertisement say ..
Always buy Concentrate, never buy something with 50 % water

MOPAR O.A.T. Concentrate,

Manufacturer Part Number	‎68163848AB

Amazon price $29.87 per gallon
10 Year Life Span

Distilled Water can be bought for a $1.50 per gallon
You can buy a Gallon of milk & reuse the jugs for a mixing tool.

1/2 distilled water & half Mopar Concentrated O.A.T. Anti Freeze

If you check all of your neighbors anti freeze mixture,
you can buy a Refractometer

 

[Dodge 1500 4X4]

Also check the coolant for combustion byproducts, there is tests that determines is exhaust gasses are entering the cooling system, that could be from the head gaskets, EGR cooler, or possibly a cracked head/block

This 100% the cooling system is getting pressurized, I would check the fluid in the overflow bottle, for now replace the radiator cap and put the proper OAT concentrate W/ Distilled water.

 

[EdGs]

If losing coolant, it is going somewhere. Getting burnt during combustion, etc.

One thing you can check is for coolant in the oil.

After the truck has sat for a day, crack the oil drain plug loose, but DO NOT remove it. Place a pan below the plug and uncrew the drain plug just enough to allow it to drip. Watch the drip. If coolant is mixing with the oil you will see it very quickly.

If you do see coolant (or water, etc), time for head gasket(s).

Just a quick check you can make.

May your repairs go smoothly.

 

[GTyankee]

If the whole system is pressurized

When the contents in the radiator is 206°F
Why don't you get steam or vapor burned when you open the Overflow/Recovery tank lid ?

 

[04fxdwgi]

Personally, I prefer the troubleshooting and start at the cheapest and work towards expensive by process of elimination. The cheapest being the checking that the system holds pressure. If that's not the problem, move to the next least expensive suggestion.

If system is not pressurized properly, that lowers the boiling point of the coolant. It also allows the coolant to escape. Under pressurized systems also will not burp out the air properly. Have seen this dozens (or hundreds) of times when I worked in shops years ago.

 

[Bulldogtt]

Good afternoon everyone Thanks for all the responses. Let me just say first that I believe usually the simplest answer is the right one. When we originally discussed this issue my first thoughts were a new rad overflow bottle cap and a t-stat. So two days ago we ordered both.
Everyone here was on the right track for sure. It ended up being the lower o ring on the cap that had been nicked a the pressure and fluid were blowing right by. Last night we replaced the cap and everything seemed fine. We talked this morning and everything is back to normal.
He figured out what happened. He had his oil changed at an aftermarket drive though shop (no names needed) and the coolant fluid level cap was removed as the worker couldn’t confirm level. when he got home the leak had started after shut down and he or I never noticed the nick until replacing the cap.
Gentleman again I appreciate all the replies and info and yes there is a flush and refill in the truck within the next two days. I told him it’s cheaper than rebuilding motor again. Lol.

 

[EdGs]

Good afternoon everyone Thanks for all the responses. Let me just say first that I believe usually the simplest answer is the right one. When we originally discussed this issue my first thoughts were a new rad overflow bottle cap and a t-stat. So two days ago we ordered both.
Everyone here was on the right track for sure. It ended up being the lower o ring on the cap that had been nicked a the pressure and fluid were blowing right by. Last night we replaced the cap and everything seemed fine. We talked this morning and everything is back to normal.
He figured out what happened. He had his oil changed at an aftermarket drive though shop (no names needed) and the coolant fluid level cap was removed as the worker couldn’t confirm level. when he got home the leak had started after shut down and he or I never noticed the nick until replacing the cap.
Gentleman again I appreciate all the replies and info and yes there is a flush and refill in the truck within the next two days. I told him it’s cheaper than rebuilding motor again. Lol.

That is fantastic. Best possible outcome.

Thank you for sharing the solution.