Coolant leak from back of head

[Silverwolf2691]

Hello everyone, first post but long time lurker. Last night i noticed a coolant leak coming from my truck on the ground while i was shopping. Was almost a 12" wet spot on the ground after about an hour and a half of sitting. After getting the truck home and letting it cool off for a bit i was able to find out where it was coming from. On the head in the back passenger corner there is a 45 degree spot that has a small hole, about 3/8" diameter. Is this a freeze plug and if so has anyone replaced it without taking the head off? Not a lot of room and its close to the exhaust so im not expecting a lot. Im also hoping to properly fix it after winter if this fix isnt long term..

 

Thanks in advance,

Silverwolf

[Mopar1973Man]

Head gasket... I just got done do that. Mine leaked at the very same spot.

 

[Silverwolf2691]

I did a head gasket a bit over a year ago put studs in and what not. Was leaking at the front on mine. Plus there is a good amount of water in that hole just above the block and head seam. Im at work right now but hopefully gonna look later tonight after spraying it down with brake clean see where its coming from.

[Dieselfuture]

If it's truly coming from the frost plug, then maybe just use one or two bars leaks tablets. Unless you think you can get that plug out, and as far as I know all plugs in that head are stainless steel. If you can get it out I'm sure there's some sort of a robber plug like a boat type with a screw to expand rubber. Not sure if you drain coolant below that level, then took like a pencil torch or just a torch lighter, get it hot enough to burn paint and dirt off, blow it clean, and use some JB Weld. Or just some brake clean and J-B Weld. Still need to get coolant below that level. 

[Guest 04Mach1]

^^ I agree the above is the best temporary short term repair^^

 

However if it were mine I would take the exhaust manifold off and replace the expansion plug that is leaking.

 

Then I would fill the cooling system back up with a high quality Cummins spec heavy duty coolant since the coolant being used now is the likely cause of failure. Using light duty gasoline automotive engine spec coolant is like putting gasoline in the tank of your diesel powered truck, it'll run but does more harm than good especially in the long term.

[Silverwolf2691]

Coolant is peak regular green coolant, a year-ish old. I cleaned up the area and it is coming from The plug not the gasket.. ive never pulled a freeze plug let alone one that small.. could i use a pipe plug and tap the hole and seal it up that way after removing the old freeze plug? Similar to what others use in the rocker area freeze plugs.. first photo is most recent, the second one is about 3 mins earlier and you can see the wetness difference if barely.. 

[Dieselfuture]

Not sure how much room you got if you can drill a hole and then see if it comes out using easy out, or something similar you can screw in there and pull, if you can tilt it sideways while pulling it should come out. Then maybe you can tap some threads in there like 8th npt and crew in a brass plug  

[Guest 04Mach1]

32 minutes ago, Silverwolf2691 said:

Coolant is peak regular green coolant, a year-ish old. I cleaned up the area and it is coming from The plug not the gasket.. ive never pulled a freeze plug let alone one that small.. could i use a pipe plug and tap the hole and seal it up that way after removing the old freeze plug? Similar to what others use in the rocker area freeze plugs.. first photo is most recent, the second one is about 3 mins earlier and you can see the wetness difference if barely.. 

 

I recommend coolant that meets Cummins CES 14603 specification. If you don't see the Cummins spec number on the back of the jug the coolant does not meet Cummins spec.

 

Not all coolants are equal.

[Cummin_N_GOIN']

@Silverwolf2691 Did you ever come up with solution for this? I have the same issue and going to tackle it this week. Somehow...

[LiveOak]

On 11/21/2018 at 7:21 PM, Guest 04Mach1 said:

 

I recommend coolant that meets Cummins CES 14603 specification. If you don't see the Cummins spec number on the back of the jug the coolant does not meet Cummins spec.

 

Not all coolants are equal.

 

Totally agree!    I just ordered 12 gallons of Shell ELC NT coolant for my head gasket job.  I was surprised to see that I could order it from Walmart and got free shipping!  

 

https://www.walmart.com/ip/SHELL-ROTELLA-ELC-NF-50-50-ANTIFREEZE-1-Gallon/342162211

 

When you figure up the cost of me driving to a place that actually carries this stuff, tax, and my time, the price is not too bad.  I have been using Shell ELC in my 2002 for about 14 years and I have been gradually keeping it up to par by drawing out a gallon at each oil change and adding a fresh gallon of the premix.  I think Caj Flynn does this and has had pretty good longevity on his trucks.  I do the same thing with the power steering fluid too.  

[Hoopster]

I just replaced these on my 24v Head, they are NOT stainless (as the picture indicates) mine is on the bench so a bit easier. I screwed a small self tapping screw and levered them out with channel locks. In the truck will be tight but I did see a you tube video where a guy did it. Youtube guy claimed 1/8" NPT pipe plug worked but it is too small after tapping there is almost no thread and certainly will leak. I used a Metric tap M12-1.5 and Dorman 090-108 Pipe Plugs (Autozone online box of 5 was $5) they are yellow zinc coated. 

 

There is six of these little plugs all down the passenger side of the head likely have to pull the exhaust manifold to get to the rest of them but that back one is sort of exposed, problem is firewall to head clearance.

 

The old one should come out easy enough but I don't think there is any way to get a new expansion/welsh plug driven in based on the lack of room, tap and threaded plug is the only way IMHO.

 

Good luck.

Edited July 31, 2020 by Hoopster

[Silverwolf2691]

I'm updating this to help anyone who needs help with what to do when this freeze plug.

 

I had access to a lower profile air drill, that is the biggest issue with fixing this while everything is together in the frame of the truck, is space or lack thereof.

there isn't much more room than a pipe tap on a ratchet. I used the drill to open up the plug enough that I could thread a tapered point bolt into it.

Tightened the bolt and wedged a crowbar against it, the plug popped out

Since the tap handle is too big, I used a ratchet to tap a 1/8 NPT thread into the head and installed a brass plug to replace it.

[Mopar1973Man]

Some needs to keep up on the coolant changes. Freeze plug only go bad if the coolant is change often enough. Once the coolant ages then the soft metals like freeze plug are the first to go. Go job on getting that plug stuff in that hole. But yeah mine gave up on that very corner. Head curl. 

 

Sorry on the head gasket. I tend to not think about the freeze plugs being I do keep up on the coolant changes and there is virtually no rust in my system. Just surface rust from being exposed to the air. 

[wil440]

I'll bet that plug rotted from the outside in, it's a mild steel plug not stainless, now going to check mine and spray it with rust converter and then grease it

 

As for changing coolant... I run Cat ELC premix in every vehicle I have ever owned, if coming up to winter the freeze numbers are low I add neat which you can get per litre here, I sample at every service and never once has the lab recommended a coolant change because it's worn out

I also service and repair Cat and Volvo big earthmoving equipment, coolant sampled every 500hrs along with every other fluid compartment, I've changed coolant a few times in a long time  on the lab results for mainly 5 reasons.

1. The stupid link between the seat and the steering wheel has used an oil jug to top up the coolant

2. Trans cooler leaking, although this is usually sudden death to a trans as the fluids always goes both ways

3. Engine oil cooler leaking

4. Nox cooler leaking

5. Aftertreatment ARD combustion head leaking

 

The number one cause is actually number 1..... the on board stupid, Cat ELC is red and goes dull when it's cream crackered 

[Mopar1973Man]

Only used NAPA, Prestone or WalMart Super Tech coolant. NEVER used distilled water in this truck. 431k miles never had one problem coolant changes are typically 75k miles. Last time I pulled the head off and look down in the coolant jacket is was just like I said surface rust of the cast. Freeze plugs look brand new yet. OEM water pump is still going. Never had an overheat condition and never had any issue with freezing. My irrigation water comes from a creek about 1/3 of a mile back and been using this water for flushing the block and refilling with coolant for the entire 18 years of this trucks life. 

 

Typically from April on the winter fronts comes off and the truck gets the engine power washed nearly bi weekly. 

Edited April 2, 2021 by Mopar1973Man