[kevin719]

I was heading out to Moab when my 06 LJ started to misfire (P0304 code), tried working on it in Moab and nothing seemed to work, I replaced the coil pack on a hunch and that seemed to make it worse, put the old coil pack back on. I replaced spark plugs and noticed the #4 plug was wet with gas, I thought I might have a stuck open injector, but I couldn't find an injector in town. Heading home the Jeep started to run even worse, I stopped in Grand Junction debating what to do, after starting the engine, it made a knocking sound for a couple seconds and I started to think the worst. I caught a ride home on a friends trailer the next day. Brought it into a shop and after putting a camera into the spark plug hole and cranking the engine, he noticed the intake valve was not opening. The tech pulled the head off and found the tappet was worn so bad that the spring inside actually protruded out of the bottom of it.

Back when I had about 10k on the engine I had this problem http://rubiconownersforum.com/phpbb3/vi ... 22&t=45470 After that work was completed I hadn't had any other problems until this trip. Now my LJ has less than 35k miles on it and the tech wants to put a new engine in it since those metal filings must have gone somewhere, and there's no telling how much other damage is done. That all makes sense to me, but now I would like to know what went on inside the engine, since I do regular oil changes with synthetic oil and check it regularly and the engine has never lost a drop of oil. I'm wondering what the odds might be if I can bring it back to the dealer and have it covered. I'm past the 3 year warranty but something has to have been going on in there for a long time. I always thought this LJ ran rougher than my previous LJ and TJ and am wondering if the work done on it a few years ago was a band aid to get them through the warranty or what.

Any help, thoughts, or suggestions would be appreciated.

 

[Jough]

Wouldn't you be covered by the 7 year / 70K mile warranty? If so, it will cost you $100 and getting alternate transportation for a week or two.

 

[toolmantim]

That pretty much sucks.

Hard to tell if the lifter was part of the problem from before...based on the amount of wear you describe it's very possible but also going to be hard to prove.

when only 1 valve component goes bad it's either easy to find the cause or almost impossible. A bent/plugged push rod, bent valve, defective lifter or rocker can be easily be the reason that one went bad, and with a little luck can be diagnosed....if the problem is lack of lubrication (oil not getting where it needs to be) or a slight defect in the manufacturing of one of those valve parts or small defect in the engine/head itself then it can be almost impossible to trace down.

If you do decide to get it repaired I highly recommend taking it to a reputable engine builder in your area. It's going to cost more than having a mechanic do the work, but having a person with the tools and knowledge and attention to detail that a good builder has should decrease your chances of the problem happening again.

Let me also throw out a little hopefully helpful advice....every once in a while you have to run that engine like it's stolen. Many people (myself included) have taken very good care of their Rubicons, it's not a sports car and speed is not it's purpose... and since almost of of what we use it for involves the engine running low RPM's those engines have a tendency to be "babied."

The engine wasn't built to run at 6,000 RPM all day long...but it should be run at the high end every once in a while so that those lifters spin properly.

A camshaft lobe is not exactly flat, it has a very slight angle that is designed to rotate that lifter in the block..or spin around. That spinning is essential for proper wear of both the cam and lifter.

Unfortunately we have many things working against us...different types of oil, trans shift points, high dollar vehicles driven by mature adults, all the power we need long before 3,500 RPM especially with that 4:1, in a vehicle that was not intended to be driven from LA to NY by anyone except Marines.

Go ahead and make that baby scream every once in a while..think of it as tough love. :wink:

 

[Eric]

yep... gotta bang 'em off the rev limiter every once in a while

 

[KaiserJeep]

IMHO the original repair was not done properly and excessive wear occurred as a result - I believe that your engine should have been one that got a new camshaft kit. Therefore the original engine is now toast along with your warranty. The dealership cleverly made an inadequate repair and now they will charge you for a new engine since you are beyond the 36-month warranty.

I would ask for an engine replacement under warranty. But be aware that engine production ended in 2006 and only rebuilds are now available. If the dealership won't cover the cost - time to upgrade to a stroker block.

 

[kevin719]

Wouldn't you be covered by the 7 year / 70K mile warranty? If so, it will cost you $100 and getting alternate transportation for a week or two.

the 7/70 from what I understand was only offered to the 2nd owner of the vehicle, if they wanted to pay for the extra coverage, not the original owner which I am. Mine came with a 3 year 36k warranty, I've got less than 36k but past the 3 years.

Thanks for the info toolmantim, I've always been a frustrated muscle car owner and have been know to try and drive it like it had a hemi in it :laugh:

 

[Eric]

read the fine print in the warranty, I may be wrong here, but if a repair was done under warranty, and the repair fails. I think the repair starts a new 3-36 on the repair.. I think this is how I would approach this with chrysler. DC replaced My soft top and back window out of warranty cost me a hun deductable

 

[KaiserJeep]

For what it's worth, you have had some very bad luck. I have owned seven of the I-6 engines including the two I still own in my 2001 WJ and 2003 TJ. I got 150,000 miles or more out of the first five engines, the worst failure was one water pump, and I had no engine internal failures at all. Number six is presently at 100,000 and number seven is at 45,000 - also with no major problems.

 

[kevin719]

read the fine print in the warranty, I may be wrong here, but if a repair was done under warranty, and the repair fails. I think the repair starts a new 3-36 on the repair.. I think this is how I would approach this with chrysler. DC replaced My soft top and back window out of warranty cost me a hun deductable

Oh I gotta look into that :spin:

 

[kevin719]

For what it's worth, you have had some very bad luck. I have owned seven of the I-6 engines including the two I still own in my 2001 WJ and 2003 TJ. I got 150,000 miles or more out of the first five engines, the worst failure was one water pump, and I had no engine internal failures at all. Number six is presently at 100,000 and number seven is at 45,000 - also with no major problems.

I know, I've often regret selling my 01 to get my 05 LJ, the guy I sold it to hasn't had a single problem with it. I think Jeep hates me.

 

[toolmantim]

For what it's worth, you have had some very bad luck. I have owned seven of the I-6 engines including the two I still own in my 2001 WJ and 2003 TJ. I got 150,000 miles or more out of the first five engines, the worst failure was one water pump, and I had no engine internal failures at all. Number six is presently at 100,000 and number seven is at 45,000 - also with no major problems.

I'm not sure it's luck anymore...I have owned 3 of those engines and maintained a couple more for friends...it's been a damn fine engine with 300,000 miles not being un-common in it's long history.

Oil differences in the last decade have affected the last run of these straight sixes I believe. The amount of cam/OPDA/lifters failures the last few years leads me to this conclusion.

I only have 43,000 miles on my current 4.0...but I expect a slightly more chance of a problem before it gets to 150,000 miles. Just going to try to stay aware of things before a failure best I can.

 

[bob1340]

I know, I've often regret selling my 01 to get my 05 LJ, the guy I sold it to hasn't had a single problem with it. I think Jeep hates me.

Bad news. Sure read a lot of failure stories on this.

Do you know what oil the Jeep has used both by the previous owner and you? It seems to me these flat tappets are very touchy on what oil is used. Ditto with gasoline. I know that motor is the last flat tappet motor built and most went to rollers back decades ago. ACEA 3 oil and good gas is a must on these motors in my opinion.

I also agree that they may have done something wrong in the repair. Regardless of what the warranty says I'd scream like a little girl in a bath tub full of worms about this.

 

[kevin719]

I know, I've often regret selling my 01 to get my 05 LJ, the guy I sold it to hasn't had a single problem with it. I think Jeep hates me.

Bad news. Sure read a lot of failure stories on this.

Do you know what oil the Jeep has used both by the previous owner and you? It seems to me these flat tappets are very touchy on what oil is used. Ditto with gasoline. I know that motor is the last flat tappet motor built and most went to rollers back decades ago. ACEA 3 oil and good gas is a must on these motors in my opinion.

I also agree that they may have done something wrong in the repair. Regardless of what the warranty says I'd scream like a little girl in a bath tub full of worms about this.

I used regular dino oil for the break in, and after that switched to synthetic, mostly Mobile 1. I didn't know about the lack of zinc in oil, and how much our engines needed it until recently.

 

[bob1340]

I used regular dino oil for the break in, and after that switched to synthetic, mostly Mobile 1. I didn't know about the lack of zinc in oil, and how much our engines needed it until recently.

I don't think Jeep did either!

Flat tappets have a lot more fiction and can create that metal to metal thing a lot quicker, New oils have different properties than the older flat tappet oils. DR D has written a bunch about this and I think the Mobil 1 High Mileage full synthetic is a good oil used in conjunction with good gas that has additives to clean the valve stems. I may be wrong, but I believe the ACEA 3 rating is what is needed to make sure you have the prper protection. For gas Shell, Chevron with Techron are all that goes into my Jeep unless nothing else is available. The gunk on the valve stems adds to the the load on the cam shaft hence increasing friction between the lobe and tappet. Just straigh gas, which a lot of places sells, does not have these cleaners/additives which are crucial. Jeep had a good engine in the 4.0. They should have upgraded to a roller tappet years ago. I don't think rollers can be retro fitting into them as there may not be room. And Jeep should of had a huge sticker/sign telling the owner to only use oil with the added zinc or whatever and the gas with additives.

 

[aogmitch]

My 04 did the exact same thing to me last Dec at just under 34K. I couldn't fix the miss on cyl 2, so took it to the dealer. They claimed it was carbon build up on the valves and said they fixed it and to pick it up. Got down the road from the dealer and it started missing again real bad, as I turned around to take it back, the clanging started in the engine. Outcome was wasted lifters with one wearing a hole through the bottom causing it to collapse. This caused the pushrods to bend. Ended up with a new cam and pushrods under warranty (my 7/70 is good til 7/2011). I got to see the parts they removed. Cyl #2 lifters and lobes had the worst damage, with #1 not too far behind. The remainder of the cam and lifters all looked normal. Total miles from start of missing til repair was about 30 miles.

 

[bbusch]

If it makes you feel better my engine was one of those that should have lasted 350K and dumped at 115K (as if one's misfortune helps anothers.. :roll: ).

Mine is an 03 and used the factory oil first 3K and then changed oil every 4k w/Mobil 1 until I hit around 84K then switched to Royal Purple due to the issues finally surfacing on our motors. Now 30K later I have a shopping cart full at Hesco for about $1500 in parts not to mention the labor tally that will surely meet that number. :-x

Thing that makes me the most upset is how much care I put into this motor to ensure it's long life. Looks like many are having this issue and lots more will have it unless they take pre measures to stop any premature damage. Change your oil pump to a high flow unit (Hesco has one that shoots the oil directly on the cam and OPDG) and change out your cam sync and OPDG to an older unit if you must (02-04 years should be good).

 

[kevin719]

Just thought I'd update this. Jack from Avenger made some phone calls to the Chrysler rep in the area, and before I knew it I got a phone call from the dealership saying they would take care of it. The dealer put in a new long block, charged me $500 and I now have a running Jeep again. I didn't blink when they asked If I would pay $500, it was way better than over 5000. So a big thanks to Jack at Avenger Superchargers and Jeep for taking responsibility and replacing my motor.

 

[desertfox1]

Total miles from start of missing til repair was about 30 miles.

mine made it about 45 miles on October 17th. (I didn't see this thread until today.)

#5 exhaust lifter and cam lobe is trashed. it's waiting on a new long block as I type this.

http://www.rubiconownersforum.com/phpbb3/viewtopic.php?f=23&t=71972

 

[CRJeepin]

Wonder if the ethanol gas is having an impact here? I've heard many reports that the ethanol is often well over 10% allowed; could be creating higher combustion temps that cause the type of pitting and carbonization you saw in your motor Doug. Could also be causing lifters to stick due to higher temps & parts expanding....