Bubbles coming from side of radiator

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Jeepwalker

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Check underneath your oil fill cap...look for a milky substance. If you see some, take a picture for us. Look inside the radiator and have someone raise the engine speed to 1200 and look for bubbles in the radiator. If you see bubbles, sniff them to see if it smells like combustion gasses. When the engine is hot and running I would squeeze the upper radiator hose. It should be hard but not super-hard. If those things are present it could point to a weak head gasket. Which in turn often over-pressurize a cooling system...which in turn finds the weakest point to let out pressure. It would be good to rule it out. More than likely it's not..but worth a quick 10 min visual inspection.

I personally would NOT replace the thermostat. But if you do, buy a Mopar new one.
 
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shon914

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Thank you to everyone here for the help and guidance! This is the first time I've replaced a radiator. As always, hit a few hiccups along the way but more or less, it went pretty smoothly.

Hiccup #1 - Petcock popped out and I got a nice coolant shower on my face.
Hiccup #2 - Took forever to get the lower hose off! My goodness. The step that I least expected to give me trouble.

Also, I always thought hose clamp pliers were a useless tool. Today, I stand corrected. I would have paid $100 for this tool.

As for the reservoir, there was a good amount of rust/sediment in that thing, hence the super dirty/dark dipstick. I gave it a good rinse. Also, there was similar residue on the underside of the radiator cap. (See photo.) Not a good sign.

The coolant that was drained had a cloudyish red/brown color. The container in the photo is white opaque so it doesn't show it well. That was one gallon. The rest landed on my face. :) I ended up putting about 2 gallons of new coolant after the install, which means this wasn't a full flush. I'm assuming some of the old coolant is in the engine and elsewhere.

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Wild one

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Thank you to everyone here for the help and guidance! This is the first time I've replaced a radiator. As always, hit a few hiccups along the way but more or less, it went pretty smoothly.

Hiccup #1 - Petcock popped out and I got a nice coolant shower on my face.
Hiccup #2 - Took forever to get the lower hose off! My goodness. The step that I least expected to give me trouble.

Also, I always thought hose clamp pliers were a useless tool. Today, I stand corrected. I would have paid $100 for this tool.

As for the reservoir, there was a good amount of rust/sediment in that thing, hence the super dirty/dark dipstick. I gave it a good rinse. Also, there was similar residue on the underside of the radiator cap. (See photo.) Not a good sign.

The coolant that was drained had a cloudyish red/brown color. The container in the photo is white opaque so it doesn't show it well. That was one gallon. The rest landed on my face. :) I ended up putting about 2 gallons of new coolant after the install, which means this wasn't a full flush. I'm assuming some of the old coolant is in the engine and elsewhere.

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Have you gave any thought to adding a bottle of RMI to it.
 

Wild one

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Didn't even know this was a thing until I just google it. I will definitely look into this. Anyone here have any first hand experience using this?
Theres a few threads on it,if you use the search function.I use it,ever since @Burla convinced me to give it a whirl.It does help keep the cooling system cleaner. I used it on my truck,the wifes 6.4 Challenger and our 300,and it's loosened up a fair bit of crap and put it in the overflow tank on all 3.
 

JHoward

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I bought the truck used about 4 years ago and have not put in any coolant myself. I bought the purple stuff 50/50 mixed for topping off in the short term and I ordered a bottle of the concentrate for when I do the install/flush. As for what coolant was/is in there before, I can't be sure. The color of the coolant that was leaking was a reddish/brownish color. Unclear if that's the dye of the coolant or from rust...

I've seen where "stop leak" added to the coolant in the radiator looked like that ... maybe someone/previous owner had a "leak" and added that to "fix" it.? ...
 
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Wild one

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Thank you to everyone here for the help and guidance! This is the first time I've replaced a radiator. As always, hit a few hiccups along the way but more or less, it went pretty smoothly.

Hiccup #1 - Petcock popped out and I got a nice coolant shower on my face.
Hiccup #2 - Took forever to get the lower hose off! My goodness. The step that I least expected to give me trouble.

Also, I always thought hose clamp pliers were a useless tool. Today, I stand corrected. I would have paid $100 for this tool.

As for the reservoir, there was a good amount of rust/sediment in that thing, hence the super dirty/dark dipstick. I gave it a good rinse. Also, there was similar residue on the underside of the radiator cap. (See photo.) Not a good sign.

The coolant that was drained had a cloudyish red/brown color. The container in the photo is white opaque so it doesn't show it well. That was one gallon. The rest landed on my face. :) I ended up putting about 2 gallons of new coolant after the install, which means this wasn't a full flush. I'm assuming some of the old coolant is in the engine and elsewhere.

View attachment 562666


View attachment 562667

View attachment 562668
This kit will pay for itself,lol.


I also have the Gearwrench version,and it honestly isn't really any better then the cheap version that i also have.

 

EdGs

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@shon914, did you run extra water through the system?

Thats alot of crud in there. How much was in the reservoir?

The next time I do mine I will do several drain and fills with distilled water, then top off with straight concentrate. Still deciding on the method, because just draining the rad only gets maybe less than half out.
 
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shon914

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@shon914, did you run extra water through the system?

Thats alot of crud in there. How much was in the reservoir?

The next time I do mine I will do several drain and fills with distilled water, then top off with straight concentrate. Still deciding on the method, because just draining the rad only gets maybe less than half out.

I did not. I thought that since I'm replacing the rad, I don't need to flush with water. If I'm understanding you correctly though, you're saying to fill with water after the install, let it run/cycle, flush again, then add coolant? In hindsight, this makes sense to get more of the old coolant out.
 

JHoward

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I did not. I thought that since I'm replacing the rad, I don't need to flush with water. If I'm understanding you correctly though, you're saying to fill with water after the install, let it run/cycle, flush again, then add coolant? In hindsight, this makes sense to get more of the old coolant out.

What you just posted, I'd do. You truck will thank you for it.

Hammer down and Happy motoring!
 

EdGs

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I did not. I thought that since I'm replacing the rad, I don't need to flush with water. If I'm understanding you correctly though, you're saying to fill with water after the install, let it run/cycle, flush again, then add coolant? In hindsight, this makes sense to get more of the old coolant out.
Yes.

I cut an old thermostat apart and reinstalled it minus the guts, then ran distilled water into the upper hose, letting it run out the bottom hose that was disconnected from the rad.
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Not sure if that would remove some of the crud from inside your system.

I am against using any flushng chemicals, too scared of causing other issues.

But filling the existing system with water and running it through a heat cycle, and repeating several times might get more of the crap out of the system so you dont contaminate the new radiator.

The gutless thermostat should allow for better circulation while you do this, just make sure you bleed the air out each time you refill with water, and after you install the new rad.

Looking back through the thread, it looks like you are pretty much done with the repair, and what you've done has to be a giant improvement over what you started with.

Looks like you did a good job on it.
 
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EdGs

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@shon914, your not the first one the drain c o c k popped out on......lol. The same thing happened to me when I did mine the first time. And yes, the coooant tastes terrible......lol.

Did you have any problems getting the old rad out, or the new one in?
 
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JHoward

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@shon914, your not the first one the drain c o c k popped out on......lol. The same thing happened to me when I did mine the first time. And yes, the coooant tastes terrible......lol.

Did you have any problems getting the old rad out, or the new one in?

... on my 2017 RAM truck with its original rad, this didn't happen ... I noticed after repairs from my frontal collision, the new radiator(after market)was not user friendly, so to speak, that to having to drain the after market rad the drain valve came out all the way and didn't drain like the original (oem) from it's drain hole ... causing an extremely messy radiator drain ...hmm, wondering on y'all's end.
 
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shon914

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Did you have any problems getting the old rad out, or the new one in?

It may have been you but someone earlier in the thread recommended removing the grill. That made it SO much easier to get to the bolts holding the A/C compressor to the rad. Once all the bolts and hoses were off, it was actually quite easy to slide it out and slide the new one in. A little jiggle left, right, this way and that way, and it was out. Of course had more coolant spilling out all over the place in the process. :)
 

EdGs

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It may have been you but someone earlier in the thread recommended removing the grill. That made it SO much easier to get to the bolts holding the A/C compressor to the rad. Once all the bolts and hoses were off, it was actually quite easy to slide it out and slide the new one in. A little jiggle left, right, this way and that way, and it was out. Of course had more coolant spilling out all over the place in the process. :)
Yeah, I think I did mention that because I had done it only a month or so before you.

I removed my rad before removiing the grille. PITA it was. I removed the grille as an afterthought to remove the reservoir and figured out afterward I should've done it first.....lol. Story of my life.

Yep, spilled alot more coolant on my changeout, too.
 
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Jeepwalker

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Use distilled water. So you don't get mineralization inside the radiator...

But I suspect you're already finished with the job...so, next time.
 

Ken226

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Use distilled water. So you don't get mineralization inside the radiator...

But I suspect you're already finished with the job...so, next time.

Given the looks of that radiator cap

IMG_6725.jpg

Using distilled water might be akin to trying to hold a t u r d by the clean end.

But, I guess it can't hurt either.

I think a coolant flush with some rmi25 or CLR would be a smart weekend project in the near future. (Then, use distilled water).
 
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Hemi395

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I meant ....distilled water for the final-fill. After all flushing, etc :waytogo:
I knew what you meant lol

Its just every time anyone has posted on here about the importance of using distilled water in the cooling system, someone inevitably chimes in saying they put tap water in 7 years ago and its been fine ever since and how distilled is a waste of money blah blah blah lol
 
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