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Return to Sender? Possible Head Gasket Leak in New TJ

OP
R
Joined
Jan 21, 2022
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26
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California
likely not. you'd lose too much pressure at the radiator. But, you could disconnect both rad hoses and pressurize the top one with the bottom one plugged. Should be able to pull and hold a vacuum that way.
Reason I asked is to determine if the PPI would've found the head/gasket issue had they also done the pressure test. Sounds like probably not as they would've just found the cracked radiator and attributed the coolant leak entirely to that.

I'm starting to think all PPIs should include a block test even if no other symptoms exist.
 

iamloganjames

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Apr 19, 2020
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Scottsdale, Arizona
Reason I asked is to determine if the PPI would've found the head/gasket issue had they also done the pressure test. Sounds like probably not as they would've just found the cracked radiator and attributed the coolant leak entirely to that.

I'm starting to think all PPIs should include a block test even if no other symptoms exist.
It should always be done if coolant is disappearing.
 
OP
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Opening up another thought process — how bad of an idea would it be to replace the cracked radiator and even possibly do the complete Cooling System Overhaul as recommended in the Resources section, but not otherwise directly address these hydrocarbons in the cooling system?

Is a small leak in the head gasket, as it seems this may be, at risk of worsening further so long as I keep the cooling system in good order?
 

Gollywomper

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Opening up another thought process — how bad of an idea would it be to replace the cracked radiator and even possibly do the complete Cooling System Overhaul as recommended in the Resources section, but not otherwise directly address these hydrocarbons in the cooling system?

Is a small leak in the head gasket, as it seems this may be, at risk of worsening further so long as I keep the cooling system in good order?
The problem with dancing with a head gasket is you never know when it could get worse. Sometimes rather quickly leaving you on the side of the road or trail.
 
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CharlesHS

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Most times with a blown head gasket you will eventually find oil in the water, but it is also possible to find water in the oil.
Have you noticed oil residue inside the radiator filler neck or on the cap gasket ?
Have you checked the condition of the oil and if there is any water in it?
 
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ItchyDong

Airframe & Powerplant LJ Mechanic
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Dothan, Alabama
Opening up another thought process — how bad of an idea would it be to replace the cracked radiator and even possibly do the complete Cooling System Overhaul as recommended in the Resources section, but not otherwise directly address these hydrocarbons in the cooling system?

Is a small leak in the head gasket, as it seems this may be, at risk of worsening further so long as I keep the cooling system in good order?
Dumb idea, especially if you can return the damn thing. If you're dumping coolant into the oil, and slowly adding more, you're hurting the oil's ability to do what oil does. You also run the risk of prematurely ruining your cat/cats by dumping coolant into the combustion chamber. Not to mention, coolant leaks don't get better. They get worse. When and where is it going to leave you stranded?
 
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Gilaguy23

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Sep 21, 2021
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A'holeville
We left Ca 4 years ago and last I knew its the law the seller MUST provide a smog cert. The exception is a bill of sale that states clearly it was sold as a no operation parts vehicle. The head gasket is one thing work/cost wise. The potential other damage from sitting with coolant in the crank or jugs could be another story. Your call on a gimme me my money back, but remember the seller told you of these problems before you bought it. Hope you got a good price on it.
 
OP
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Jan 21, 2022
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Location
California
Most times with a blown head gasket you will eventually find oil in the water, but it is also possible to find water in the oil.
Have you noticed oil residue inside the radiator filler neck or on the cap gasket ?
Have you checked the condition of the oil and if there is any water in it?
Oil looks good. Coolant was completely empty so don't know about oil in it, but I don't see residue inside the radiator filler neck or cap gasket.

Seems like if there is a busted head gasket, it's minor.
 
OP
R
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Jan 21, 2022
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Location
California
Dumb idea, especially if you can return the damn thing. If you're dumping coolant into the oil, and slowly adding more, you're hurting the oil's ability to do what oil does. You also run the risk of prematurely ruining your cat/cats by dumping coolant into the combustion chamber. Not to mention, coolant leaks don't get better. They get worse. When and where is it going to leave you stranded?
This is what I expected but didn't hope for.
 
OP
R
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Jan 21, 2022
Messages
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Location
California
We left Ca 4 years ago and last I knew its the law the seller MUST provide a smog cert. The exception is a bill of sale that states clearly it was sold as a no operation parts vehicle. The head gasket is one thing work/cost wise. The potential other damage from sitting with coolant in the crank or jugs could be another story. Your call on a gimme me my money back, but remember the seller told you of these problems before you bought it. Hope you got a good price on it.
Yep. Seller must still provide a valid smog cert (from past 90 days). I knew about the coolant and oil leaks, but it wasn't sold as a non-op / parts vehicle. Legally, I believe I could've had the seller reverse the sale (to say nothing of actually going through that process if they didn't agree).

I slept on it and decided to keep the Jeep. I've been looking for a TJ that fit all of my criteria for several months and I'm happy with this one and the deal I got on it. So even if I do have to do more work / spend more than initially expected to fix a head gasket problem, I'm still ahead and have a sweet car that I'm otherwise stoked on.

Thanks for everyone's input here! Looking forward to getting the repairs squared away and then moving on to the fun stuff.
 
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Honest_Abe74

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Take off oil filler cap while is running (and at full operating temp) and look down at the head with a flashlight. You will be able to see if the head is cracked usually. Little white bubbles in a line along crack.
OP, this is very likely your issue, especially since it sounds like the Jeep was overheated. 2000-2001 Jeep 4.0s are well documented for having issues with cracked heads (faulty 0331 casting) which while not common, nearly always happens if the Jeep is overheated. I’d really look into that first. If it is cracked, Clearwater replacement heads are a well-known replacement or see if a locally sourced TUPY head from a later year 4.0 can be found. The good news, it sounds like your Jeep runs well still so it is likely all you need is to get the head replaced and you’ll be good to go for many more miles. In the future I’d recommend sending off your oil to Blackstone labs for analysis. They will give you a comprehensive breakdown on your engine health.
 
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bucky

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Dec 25, 2020
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SoCal/North Dakota/ N Az
I would just fix it and pay the stupid tax if you got it at a good price. I bet the seller already spent your money and getting it back will be difficult. Sometimes you have to pay for an education. Replacing a head gasket on a 4.0 is not that hard. Check out youtube and see if you are up to it. You might be surprised and you can gain some Man Points for doing it yourself. Hardest part is torquing the head bolts properly.
 

JKP

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Aug 20, 2020
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Warner Robins GA
This is what you don't want to see:

If you see this through the oil fill, the head has already been replaced:
1642902468661.png
 

Fishtaco

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Sep 29, 2020
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Any vehicle without coolant/fluid in the header tank and radiator is a walk away unless you are willing to spend on fixing any problems that may have occurred due to overheating and fix them immediately before using it, if it was just the radiator cracked the OP would have had it fixed because the cost of a new radiator is cheaper and easier than trying to convince a potential buyer its just a small coolant problem.

it is not good if this engine has been run with zero coolant because you have no Idea if it has been cooked or not and how many times just to get the PO home or off a beach/trail.

You seem happy to have the work done though, I don't have smog tests where I come from but if you are required to have a smog certificate before sale and you have not got one then there is a reason it hasn't got one and it could go beyond the coolant/head gasket/head problem.

Does your mechanic believe it will pass smog once you have fixed the radiator and head? I am sure they would have checked for water in the oil or oil in the radiator already because that's the first thing they would have looked at before doing any other tests.

Just my opinion :)
 

bromel

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You need to look at it this way: You must replace the cylinder head no matter what. By far the most likely scenario is that you have a cracked head, as all 00-01 engines are prone to. If by some chance you have a bad head gasket, you should still replace the head. The standard advice with non-TUPY 0331 heads is that if it comes off for any reason, never put it back on again. Buy a Clearwater for $600 and call it a day.
 
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