Hello all,
I recently got myself a Jeep JKU X. Its got a lot of miles (150k) and has been leaking coolant since I got it a couple months ago. I'm 99% sure the intake manifold gasket needs to be replaced, but am wondering if thats all thats wrong with it. My oil seems to be normal in color and there isn't any buildup on the radiator cap, but it seems like the head gasket is sticking out slightly at the front of the drivers side head. I'm not sure if this is normal or not (pics below). Also, there seems to be a lot of green/yellow gunk buildup on the area near the oil pan/crank case. The coolant in it is green, which is different than stock I think. Do you all think this could be caused by coolant leaking down the block or do I have a bigger problem? Thanks in advance for your help, I'm trying to learn as much as I can about this jeep!

 

Welcome.

If the coolant is green it's likely the wrong stuff. The recommended coolant is HOAT (zerex G05). Color isn't reliable but HOAT is usually yellow or orange.

I can't see the pictures too well (on my phone). But the intake manifold gasket is know to leak coolant on the 3.8.

You can pressure test the coolant system. Or test the coolant for exhaust gasses (low pH). Or have a sample of oil tested for coolant or fuel.

Hopefully it's not the head gasket but jeep an eye on the temp gauge, which is really more of an idiot light than a true gauge.

 

That's an after market head gasket. Pressure test the cooling system to see exactly where it's leaking. After you repair the leak do a complete flush of the cooling system and replace the antifreeze with the correct fluid.


Sent from my iPhone using Tapatalk . Rich

 

Thanks guys, I'm going to be replacing the intake manifold gasket over christmas break so I will change the coolant to the one you recommended, hopefully that solves all my problems.

 

You probably have one of three issues:
1. Intake gasket, as you have suggested. That's the most likely culprit.
2. Rear freeze plug. The 3.8 has 2x on the rear of the block.
3. Cracked block.

My JK began leaking coolant from the rear of the block and dripped through the bell housing at 40K miles. I guessed #2 and added some Bars Leak to the radiator to fix. That worked well for another 40K miles. Then the engine began to noticeably lose power and smell of coolant. When the engine was pulled, it had a major crack on the rear of the block. That's why I now have a V8 in the Jeep.

From your pics, I'd go with the scenario #1.... which is also the cheapest and easiest to repair

 

I have a coolant leak in the same are, what was the problem on yours

 

I had the same slow coolant leak..was intake manifold gasket..I was nervous to replace it myself in the middle of winter so my local shop did..it came to about 500$ Canadian