Jeep Engine Question, Please Help!

[XJ]

My jeep cherokee 2000, is overheating and I took it to me mechanic and he said it is the head gascket, and he will open the head to see what is going on.

So is it better to change the engine rather than doing the head gascket? because my firend tell me that they will never do it correctly escpecially i use the car for offroading.

Also one of the cylenders is week and my mechanoc tells me also if you need overhaul do it rather than installing another used engine becuase you do not know the situation on the used engine.

Can you help please i am not sure what to do and also how much the used engine cost?

Also since the wrngler engine is the same as my engine what models fits as my engine.

[Chuck]

Hi Khaldoun,

cool down. If it is the head gasket you can measure it BEFORE OPENING THE ENGINE by checking if you have CO2 in the cooling water. Also you can see it on the colour of the exhaust pipe inside. Check this for more info.

http://www.arrowheadradiator.com/head_g ... k_test.htm

If your gasket is really gone it will be not that difficult to replace it. The engine is not so difficult to repair. Check with Doc i would say, he can give you more info.

How many kilometers do you have on it now ? If it is not making noise from knocking pistons i do not see problems to let it be in. If you change to another used engine you also do not know what will come up. 8O

As an idea, i still have my old 99 engine. You can build up a nice Stroker from it and change it with yours.

The Wrangler engine is the same as in the XJ.

Good Luck Buddy.

[WildFire]

Khaldon,

What is the chance that the tempreature gage is giving a wrong indication?
I remember that before it did.

Is there any Cooling water mixed with the engine's Oi?
As far as I know this indicates that there is a problem with the gasket or with the engine head.

Now,

Changing a gaskit is not a big deal, but changine the engine head would cost big $$$ if you are going for a new one. (if the engine head is cracked , dont repare it .. you need to replace it)

A STROKER ..... thats a nice idea :iagree: as long as you need to overhaul the engine.
on the other hand buying a used engine is cheaper(cost around 2 to 3 thousand from scrap yard) but, you will never know its condition till its fixed and some times when its too late :badidea:

I know that my knowledge in mechanics is very shallow but, that is what i know .

All the best

[XJ]

Hi Khaldoun,

cool down. If it is the head gasket you can measure it BEFORE OPENING THE ENGINE by checking if you have CO2 in the cooling water. Also you can see it on the colour of the exhaust pipe inside. Check this for more info.

http://www.arrowheadradiator.com/head_g ... k_test.htm

If your gasket is really gone it will be not that difficult to replace it. The engine is not so difficult to repair. Check with Doc i would say, he can give you more info.

How many kilometers do you have on it now ? If it is not making noise from knocking pistons i do not see problems to let it be in. If you change to another used engine you also do not know what will come up. 8O

As an idea, i still have my old 99 engine. You can build up a nice Stroker from it and change it with yours.

I have 150,000 KM on the clock, but remember I bought the car used and i do not know how the pervious owner treated the car, which i think not really well.

But it is over heating for sure in my last offroad trip it over heated to red 3 times and each time the cooler was gone, and i show it to my mechanic and he pressed on the radiator hose and it was too hard and since i have new water pump and radiator and thermostate few months ago, the only thing is the head gascket is the the problem, it is NOT mixing oil and water and as he explained it is mixing water and co2, once he open he will find out.

but as far as the fixing it, you think it will be the same as original and it will handle offroad trips and pressure and heavy duty offroading?

Man i wish i can get a strocker but i do not want to spend 10-12k now, that is the problem.



The Wrangler engine is the same as in the XJ.

Good Luck Buddy.

[DiVeR]

Khaldoun, i just dropped my car to the mechanic 2 hours ago for the same problem. this is the second time i give it to him this week for the same reason

[XJ]

Khaldoun, i just dropped my car to the mechanic 2 hours ago for the same problem. this is the second time i give it to him this week for the same reason

Diver, I sad that you have the same issue, but i guess it is a jeep thing, I am pretty sure 99% that it is the head gascket, because all other parts is new which i did install it few months ago (water pump, radiator, thermostate, radiator hose) also when it is running and it is hot regular tempreture 100, try to press on the upper radiator hose if it is hard i think you have the same issue.

Any way tomorrow my mechanic will open the the head and see what is happening and i will keep you posted with progress.

[DinoStroker]

I hate to tell you this but the cylinder heads in 2000-2001 model 4.0 Jeeps is prone to crack in the middle between the no.3 and no.4 exhaust ports (the hottest part of the head). This usually happens after the engine has passed the 100,000km mark and it's out of warranty.
The first sign of trouble is a mystery loss of coolant. Eventually the rate of coolant loss increases and you have to keep topping up the overflow reservoir. The coolant goes into the crankcase and mixes with the oil. If you remove the oil filler cap, you might see a chocolate brownish sludge between the exhaust valve springs of the no.3 and 4 cylinders. The engine may intermittently misfire if the coolant enters a cylinder and wets a spark plug. Remove the spark plugs and see if one or more looks a rusty brown colour.
If indeed the head IS cracked, replace it with a used head from a '96-'98 4.0L engine. These are much better than the '00-'01 pieces of junk. This is also an opportunity to port the replacement head for a few more HP and build a stroker. I love mine, and Chuck built his stroker using my old 4.0L engine that I sold to him. I bet he loves his too.

[vikid]

Hi Khaldoun,

cool down. If it is the head gasket you can measure it BEFORE OPENING THE ENGINE by checking if you have CO2 in the cooling water. Also you can see it on the colour of the exhaust pipe inside. Check this for more info.

http://www.arrowheadradiator.com/head_g ... k_test.htm

If your gasket is really gone it will be not that difficult to replace it. The engine is not so difficult to repair. Check with Doc i would say, he can give you more info.

How many kilometers do you have on it now ? If it is not making noise from knocking pistons i do not see problems to let it be in. If you change to another used engine you also do not know what will come up. 8O

As an idea, i still have my old 99 engine. You can build up a nice Stroker from it and change it with yours.

The Wrangler engine is the same as in the XJ.

Good Luck Buddy.

hey XJ... i agree with chuck's approach.. just pray that only the gasket is gone and you should replace it in a non bangali WS; if you buy a used engine how will you know what is wrong with it and may be its been used by a XJ alike..

forget abt stroking it; my advice...

[XJ]

I will not strock it for now, it is not in my budget plus it will take some time to do it which i dont.

I will find out soon what is going on.

[XJ]

Okay, the mechanic opened the head and the result as it was expected; the head gasket was burned but thanks god that every thing else is good, so i changing the gasket and i will take the head to resurface and to be checked under pressure to make sure that it is okay.

So Diver i guess you have the same issue if you want i can send u to my mechanic.

[XJ]

Okay, bad news again, the mechanic told me that the head is cracked, so i guess i need new head.

So the question here is it better to put new engine or just get a used head and fix it and put new head gasket?

[XJ]

I hate to tell you this but the cylinder heads in 2000-2001 model 4.0 Jeeps is prone to crack in the middle between the no.3 and no.4 exhaust ports (the hottest part of the head). This usually happens after the engine has passed the 100,000km mark and it's out of warranty.
The first sign of trouble is a mystery loss of coolant. Eventually the rate of coolant loss increases and you have to keep topping up the overflow reservoir. The coolant goes into the crankcase and mixes with the oil. If you remove the oil filler cap, you might see a chocolate brownish sludge between the exhaust valve springs of the no.3 and 4 cylinders. The engine may intermittently misfire if the coolant enters a cylinder and wets a spark plug. Remove the spark plugs and see if one or more looks a rusty brown colour.
If indeed the head IS cracked, replace it with a used head from a '96-'98 4.0L engine. These are much better than the '00-'01 pieces of junk. This is also an opportunity to port the replacement head for a few more HP and build a stroker. I love mine, and Chuck built his stroker using my old 4.0L engine that I sold to him. I bet he loves his too.

You were right it is cylinder no 3+4, the gasket was damaged at those cylinders.

So the question here is it better to change the head and it will live good, or change the engine?

I am affraid that it does bad again after a while

[DinoStroker]

Like I said in my last post, find a good used '96-'98 head that has casting no. 0630 stamped on it. Even an earlier '91-'95 head with casting no. 7120 will do nicely (you'll just need to plug the hole for the coolant temp. gauge sending unit). Take it to an engine shop to have it skimmed and the valves/valve seats lapped, and you'll be good to go again.
This cracking problem with heads on the 2000 model 4.0 engine is so common that Chrysler should have issued a recall to replace the defective heads. Needless to say, they didn't and I'm sure they knew about the problem.

[vikid]

just change the head as Dino said and as PPNATH did; may be he could share his experience

[DiVeR]

I'll be getting a word from my mechanic maybe today or tomorrow for the same problem. Most probably will have to do the same.

Anyway thanks guys for sharing your info & experience.