2010 jk radiator

mark sr

Member
I need to flush the radiator on my jk but can't find the petcock anywhere, am I looking in the wrong places or does it not have one?
 

I need to flush the radiator on my jk but can't find the petcock anywhere, am I looking in the wrong places or does it not have one?
Passenger side of the radiator. Need a pic?
 
jkcooling-1.jpg
Sorry drivers side 1/2 way up #2 in the diagram.

imagesashxi4WD_JEP4644269jpgpartNoJEPw33-1.jpg


4wd.com
 
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Either mine isn't the same as the diagram or it's hid mighty good. My youngest son came up to work on his Bronco and he couldn't find it either. I guess I'll hold off and have his brother look at it next week. Worst case scenario I could take the bottom radiator hose off and just top of the radiator with fresh anti-freeze. I don't know why but the bottom hose is almost half way up the radiator.


JPN,
I forgot to thank you for the schematic even though it doesn't seem to apply to my jeep.
 
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Either mine isn't the same as the diagram or it's hid mighty good. My youngest son came up to work on his Bronco and he couldn't find it either. I guess I'll hold off and have his brother look at it next week. Worst case scenario I could take the bottom radiator hose off and just top of the radiator with fresh anti-freeze. I don't know why but the bottom hose is almost half way up the radiator. JPN, I forgot to thank you for the schematic even though it doesn't seem to apply to my jeep.
The bottom half of the radiator is a transmission cooler.

Here is another image and it(#2) is on the same side as the radiator cap(#1).
409055d1338834841radiatorflushradiatordr-1.jpg
 
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So below the bottom hose is all transmission cooler? That makes for a small radiator. It does get up to operating temperature quicker than anything I've ever driven but it never overheats so I guess it works. I've got to go to the eye doctor this morning but I'll check again when I get home. thanks again!
 

The bottom of the radiator. The bottom hose is still engine return.
 
Thanks for hanging in there with me JPN!

The drain plug is on the passenger side as shown in post #6 The only way I could access it was to remove the splash pan which is held on by 6 of those stupid one use plastic screws. It's difficult to get your fingers in there to turn the drain plug and even harder to get it started to thread back in. I don't think I've ever worked so hard just to flush/fill a radiator. BUT it's flushed and filled with new anti-freeze!
 
Glad you got that taken care of.

Ya I don't know why the diagram is wrong unless there are different versions. Manual vs auto?? Ref vs unlimited?? They are all the same engine??

Just be sure you burp out the air if you drain the
system or you will overheat and boil over. Also make sure your overflow is filled to the cool line.

Also what type of antifreeze? Brand and type? It makes a big difference!! Some will clog your radiator over time.
 

What is it about jeeps that make it so hard to burp the air out of the cooling system? My xj was the same way but with all the other vehicles I've owned or worked on it never was a big deal. While I believe I got all the air out I will be keeping an eye on it the next few times I drive it.

I used autozone's 5yr, 100k, universal coolant.
 
Typically burping is best done on an incline or by jacking up the front of the jeep. Removing the radiator cap. Starting the engine and allowing it to come to temp where the thermo opens and coolant flows. Then squeeze the top radiator hose to help the bubbles through. Be careful not to get burned. After the 20-30 bubbles stop coming out, shut the jeep off and let it cool. Fill the radiator and replace the cap. Fill the overflow to the cool mark and lower the jeep.


As far as coolant your manual should specify the recommended coolant. It likely says to use HOAT (Hybrid Organic Additive Technology). You could go to the dealer or get Zerex G-05. The AZ brand is not HOAT read the label. Unless it states HOAT it isn't.


Now for the bad news. GM made a coolant DEXTRON that clogs radiators. I think they still use it but service engineers will not recommend using it. Not sure if AZ is a relabel of this. Also I've read of some mixes of coolants interacting and causing issues, though I've not experienced it myself. So if you just drained the radiator and filled the ~3/4 gallon in the engine was mixed with the 'new' fluid.

To fix this potential. Completely flush all the fluid. Don't just drain and fill. If you have low hardness tap water drain the system and run your hose with a flow equal to the drain or remove the top hose from the radiator and run the engine until all the fluid coming out of the engine is clear. Drain and fill with HOAT. Keep in mind the engine holds a 3/4 gallon of fluid that doesn't drain, so you can adjust to end up with the desired mix. At this point use distilled water you could buy at the grocery.
 

It was just regular maintenance - should have done it last year :redface:
For the most part I squeezed both top and bottom hoses along with adding coolant as it lowered. After getting most of the gallon in I let it rest awhile and then repeated. I went to town today with a jug in the back expecting to need it but I most have burped it pretty good :cool:

HOAT coolant is dealer only around here. The AZ coolant claims to be compatible with all kinds/color of coolant. While there were a couple different brands it's about all any of the local auto parts sell now. I've used it for years on my wife's merc and stepson's jeep liberty [both aluminum block/radiator] with no issues.
 
G-05 isn't available at our local stores. Not sure if NAPA has it but that's on the other side of the mountain. I know some say HOAT only and the universal is bad while others say the universal fluid is fine. I've not had any issues with it so I'm inclined to keep using it. After double checking the AZ coolant label - it's 5 yr, 150k rated.

HOAT was original to my 2010 jk, they switched to OAT in 2013 [?] I used a cooling system cleaner and then rinsed multiple times so I'be surprised if 99% of the HOAT wasn't removed so there shouldn't be an issue of the two being combined.
 
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