Engine Head Cracked - Rebuilt or New Engine? Interesting Story and need help!

[Jeep Girl]

Hi,

I learned today that the engine head of my 2000 Jeep Wrangler is cracked and the entire engine must be replaced. About 2 months ago, I saw the Check Guage Light coming up intermittantly and when I finally checked under the hood, I found that the Coolent was totally empty and the coolent cap was off. Of course, I refilled the coolent and kept an eye out on guage light. A month later, I noticed the light again... but this time, I also noticed that the oil pressure was dropping whenever the car was idle. So, I looked under the hood and to my surprise, I found the coolent was completely out again. After refilling the coolent, AND checking the oil which seemed to be full enough... I decided to take it the dealer.

It turns out that the engine head is cracked and the coolent has been draining into the oil and getting into the engine. I purchased the extended warranty (thank goodness) and luckily, the entire thing is covered in the warranty. (By the way, I have never observed the engine overheat (I take care of my jeep) and was surprised to hear the dealer tell me that this is not an unusual problem with this engine!! He was SOO matter-of-fact about it!)

My question is this: Should I have them replace the engine with a rebuilt engine or a new engine? The dealer told me that they offer a 3 year 30 thousand mile warranty on the re-built engine and only 1 year and 12 thousand miles on the new engine. That doesn't make sense to me but for now, I have instructed the dealer to replace with a re-built engine.

Does anyone have any guidance for me? Thanks very much!!

~Jeep Girl

[xj31]

If its a mopar reman engine you will be fine.And yea,it is common for cylinder heads to crack on a few years,like 2000 and 2001.usually the crack is right in the center of the head right under the oil cap.I heard it had something to do with the way they got the sand out of the castings.Supposedley they would just throw a bunch of raw castings in like a big drum and spin it and let them tumble all the sand out.Then they figured out that this was cracking the heads.I guess cast iron doesn't like bouncing around.I can't prove that to be true,it's just something I heard.But any ways the mopar reman motors are usually really good.and you can't beat the warranty.plus any chrysler jeep or dodge dealer will honor the warranty so if it blows up you pay nothing.Just make sure it is a mopar engine if its something else the warranty might only cover the part and leave you responsible for the labor if it blows up.Also they don't actually make a new engine for your jeep.It would be a new block and a new head that they assemble at the dealership.

[Jeep Girl]

Hi xj31,

Thanks so much for the reply. I was worried that the dealer might just be handing me a line. It's good to know that I'm getting good info from them.

THANKS AGAIN!

Jeep Girl

[wilfie27]

xj31 is right about that particular head, the one with the 0331 casting. I handle cylinder heads on a daily basis and 2000+ 4.0L is prone to cracking inbetween the rocker posts and is unrepairable except for heat welding. 4 out of 5 are usually cracked. A Jasper Engines head will be reinforced in that area to prevent future cracking.

[Jeep Girl]

THanks for the great information wilfie27! 4/5 is a really high ratio. I just received my jeep back from the dealer and to my surprise the oil gauge is fluctuating still. i'm taking it back but i will make sure to ask about the Jasper Engines head to make sure I don't go through this again. Interestingly, this occurred during my extended coverage period and my fear is that with the reman engine, it will happen again after the warranty expires (3 years 36K miles). thanks again for the information! Anita

Originally Posted by wilfie27

xj31 is right about that particular head, the one with the 0331 casting. I handle cylinder heads on a daily basis and 2000+ 4.0L is prone to cracking inbetween the rocker posts and is unrepairable except for heat welding. 4 out of 5 are usually cracked. A Jasper Engines head will be reinforced in that area to prevent future cracking.

[Jeep Girl]

Wilfie27,

Quick question for ya.. how do check to determineif a Jasper engines head was installed with my engine? I asked and the mechanic at the dealer didn't know anything about it. They kinda gaveme the run around b/c i'm a girl.... Can you help?

Jeep Girl

Originally Posted by wilfie27

xj31 is right about that particular head, the one with the 0331 casting. I handle cylinder heads on a daily basis and 2000+ 4.0L is prone to cracking inbetween the rocker posts and is unrepairable except for heat welding. 4 out of 5 are usually cracked. A Jasper Engines head will be reinforced in that area to prevent future cracking.

[fredjacksonsan]

Ask the dealer for an extended warranty on the engine after they do the repair.

[wilfie27]

Originally Posted by Jeep Girl

Wilfie27,

Quick question for ya.. how do check to determineif a Jasper engines head was installed with my engine? I asked and the mechanic at the dealer didn't know anything about it. They kinda gaveme the run around b/c i'm a girl.... Can you help?

Jeep Girl

Sorry for the delay, holidays and all, I'm sorry I didn't make myself clear on on my orginal quote. Jasper Engines doesn't sell just the head but the whole engine. If it was a Jasper remanufactured engine it will be painted grey and have an emblem sticker on the side of the block.

The mechanic should be able to tell you where the engine came from. The crack has to be "heat welded" because the crack is "in the water" and can't be welded or pinned using traditional methods.

Heat welding is a process where the head is heated up to around 1200 deg and then welded. Very few places do this process.

In the water means there is coolant on the other side of the crack. When the vehicle is up to temperture there is a lot of pressure and it can seep past a weld or pins and into the oil.

Sorry if too much info. But Jasper does have a 3/36 warranty.