he communicated the following to me; diagnostics is telling me you have a blown head gasket and you're missing on one cylinder
His recommendation was to replace the engine with a used or rebuilt one.

Any thoughts....comments?

Get a 2nd opinion. The mechanic's conclusion that "this engine is shot" and "replace the engine with a used or rebuilt one" due to a computer diagnostic and a misfire in the #1 cylinder would have me running to another mechanic.
(fwiw, I would not replace an engine with only 140,000 miles if all that is needed is a head gasket.)


And Welcome to the Jeep Wrangler Forum!

 

I am not a mechanic and it is possible he is correct....the biggest thing holding me back on this is the longevity the 4.0 is known for...I feel that when the head comes off he can see if there is obvious internal engine damage...wondering if he could run pressure check with blown head gasket I don't think so but might try? little help here fellas this doesn't sound right to me....am I the only one thinks this is a little off?
If no one else chimes in ask him what the charge is to pull the head...and decide if that is a cost you can afford...to see the internal top of the engine...between that and dropping the oil pan you should be able to see what is wrong.....if anything is wrong inside motor....

 

A blown head gasket by itself is not that serious, it only requires the head be pulled to replace it. I'd assume the engine is ok until after the head gasket is replaced and you find out otherwise.

I'd go to a shop that specializes in Jeeps, not the dealership, and get a second opinion. I'd also look for a shop that is a member in good standing of the Better Business Bureau. Not being a member doesn't mean they're dishonest, but being a member of the BBB is at least a plus that they are likely honest.

 

With just 140k miles and if engine has been serviced regularly and not beat to death, my bet would be on keeping what you have, replacing the gasket after getting head reworked (milled, valves cleaned up and/or ground or replaced, as needed, new guides,etc.), and keep on ''jeepin". This would be a whole lot cheaper than a complete engine replacement. Good luck!

 

With a blown head gasket, it all depends on how its blown, Water in oil? Compression leaking? the gasket failure is key.
If ANY water gets in the oil, and it is run, bearing damage can happen QUICKLY!
If its a compression leak (between cylinders) it COULD burn the metal out of the head, tear~down is required to see, if there is metal missing, you need a new head, if not, machine it and verify the deck is still flat (block).

Oil leaks are rare, but usually result from a crack, or blown gasket, but depend on the leak source.

IMO: DEFIANTLY get a second opinion, and DO NOT drive it. Tow it...

 

Different mechanic....FOR SURE.......

Blown head gaskets are RARELY fatal. In the past, on straight sixes, we have used TWO head gaskets to fix issues. Not recommended, BUT, when you do not have access to a shop, ya gotta do whatcha gotta do...........

Have head removed........ get it machined and have a COMPETENT mechanic look at block side and measure for flatness and/or scoring. in the UNLIKELY event you have either, there are measures that can be taken to mitigate even THOSE issues.

Measure your wallet for flatness too.... none of this is gonna be cheap.

 

The 2000's were also prone to cracked heads, I think that's more common than a blown head gasket. It's still a lot cheaper to fix than replacing the engine as long as you haven't had coolant in your oil so long that everything is trashed. Has you oil pressure been OK lately?

 

Oil Pressure has been fine...high if anything. I'll need to wait till tomorrow (1/2/2013) to find out if there is water in the oil. I think I need to find a good Jeep mechanic in the Savannah area and get a second opinion.

 

Ahh Savannah, my home town!
If Mitchells Automotive is still around, they do good work. Althoug this was in the early 1990s. Havt been back in Ga in 10 years though.

 

Overheating + blown head gasket may be indication of more serious issues. You may have a warped or cracked head. You may also be getting coolant into the combustion chamber and / or oil and it is burning off before it builds up too much. Coolant in oil = bad for your bearings and if the coolant pools into the cylinder on top of the piston while shutdown and you crank it over while it is in there....

 

The crack prone 2000 head does not cause low oil pressure it lets coolant into oil and that destroys lubrication even with normal oil pressure

Look for oil in water and inspect for the hair line crack also were you having to add coolant

If you do have a cracked head and ran it with coolant mixed in oil you Lilkly you need a complete rebuild or engine replacement

This was an issue with the 4.0 2000 head redesign and was fixed with TUPY head redesign about 2002

Do a search on TUPY heads

 

Time to get a Cummins...

 

Pretty simple test for coolant in Oil..... pull your dipstick....... does it look like a chocolate milkshake????

If so, probably coolant in oil....... if it looks like oil.... probably not.....

 

Except, if it has not been run, you wont see any milkshake, and oil floats on water, so, is it overfull? If so, crack the drain plug, if ANY water comes out (or coolant), do NOT start it, tow it to a place to verify the head gasket is out, and have them repair it.

 

Last year my 1998 4.0 overheat.. Towed to a shop .. The guy found a cracked head.. I ended up replacing the water pump, thermostat, gaskets and of course a "new" head.. All good now.. I read at the time it was kinda "common" for the head to crack ..

 

Def get a second opinion. Even having to machine/replace head is cheaper than total replace/rebuild.

 

….and unless you buy/build/re-build the engine yourself (or know/trust the mechanic), you never know what they put in your TJ.

 

If the head did crack make sure the replacement has TUPY letters cast into it

If there is water/coolant in oil you may have much more damage and expense then a head or head gasket

 

Thought I'd provide an update, since everyone was so helpful. I ended up towing it to the The Jeep Specialist of Savannah. Chris, the owner, is a great guy. He quickly told me the head was cracked and for $1,100 I was back in operation (including replacing the head, towing, replacing a cracked thermostat housing (original issue), and pulling the security alarm out of the jeep. When I first told him the problem and what the first shop had recommended, he said, some people are jackasses... I knew I was in the right place. Thanks for all the help.

 

That's great news! Sucks about the first mechanic...lots of slime balls out there. Sounds like he took you for a radiator, that you probably didn't need, a thermostat that again you probably didn't need and then re-installed the broken part that caused the issue to begin with--I agree with the second mechanic, WHAT A JACKASS!

$1,100 for all the work the second mechanic did sounds like a very fair deal.

As for comments about milkshake oil--that doesn't necessary mean you've toasted your engine. What it does mean is that you need to have the bearing clearances checked.

 

Glad it worked out hopefully the replacement head is an improved design over the problematic Chrysler 2000 design that was significantly resolved with TUPY redesign

Sounds like a good price considering parts and labor

Hopefully you did not have significant coolant in oil for long enough to significantly increase wear on bottom end of engine

 

Wanted to take the time to thank everyone for sharing info. I've been a user of info but never a giver of info and decided to change my ways. I'm not a mechanic but must try turning wrenches to keep vehicles going now that daughters are old enough to drive.

1998 TJ 2.5L with 104k miles.

The jeep was in the garage and we would pull behind RV for a peace of mind in case RV laid down on side of road. Other than that we would drive occasionally when a friend would call because they went somewhere they shouldn't have tried going and needed help getting out. Recently the Jeep has been the daily driver for my daughter. The jeep was loosing about a quart of coolant/water every couple weeks due to minor leaks in hoses or so I thought until one day when the Jeep over heated. I fixed what I thought was a leak in the hose by replacing both upper and lower hose. couple weeks later I checked the oil and it was milky. I started google searching to see what needed to be done. After realizing removing the head and replacing the gasket needed to be done I took Jeep to local mechanic. I also knew replacing the motor may be required. If I knew then what I know now I would have gone straight for the remanufactured motor option which at the time seemed to be the most expensive way to go. knowing the bearings could be a problem at some point I chose to go with having the head machined and a valve job done based on the mechanics visual inspection revealed no problems and compression checked out ok. the machine shop pressure tested the head and found no leaks so it was determined the head was still ok. had machined head installed and couple days later the Jeep over heated again. Turns out the head had a crack in it the machine shop missed. machine shop replaced the head and gaskets. still willing to take a gamble I had the replacement head installed but there was still a ticking sound. A day later a knocking started so I took back to the mechanic. cylinder compression checked out but it was determined a lobe on the camshaft broke off or ground down to where the piston would go high enough to lift a valve (i'm not a mechanic so my description may be a little off).

Long story short. If I had to do over again I would go straight to the re-manufactured motor option. I found a re-manufactured motor for $1,800.00 that included 7 year unlimited miles no fault warranty for the motor and $55.00 for labor to remove and replace if determined something wrong with motor. I paid $1,300.00 for the labor to swap motors. I forget what I paid for the head to be removed, machined with valve job, and reinstalled but I want to say it was somewhere around $800.00. I don't know exactly because I had a new radiator, hoses, heater hoses, and water pump installed too.

I will be making a new post about the re-manufactured motor install because when it was installed there was a vibration at idle and the only way to eliminate the idle was to release the transmission from the mount so motor would relax and not bind when secured to the motor mounts and transmission. Once the motor was secured to the motor mounts the transmission moved forward 1/2". Unable to determine why this happened or if this is a common tolerance between 2.5L engine block motor mount bolt hole locations. I'm heading to mechanic to measure the original block before sending to the remanufacture company. the company selected the reman motor using the VIN number of my jeep.

Thanks again for all the information I've obtained from this Forum to help keep my Jeep running.