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The first thing you need to do is determine what exactly the problem is... you can isolate which cylinder is ticking with the engine running and a stethescope or ear against a long screwdriver on the valvecover.

How many miles/what kind of mechanical condition and what year is your jeep?

Have you ever changed your oil?

does the problem cause a noticable misfire?

is the problem persistant? intermittant? or does it happen only when you first start the jeep cold?

do you let your engine warm up before driving?

Are you sure its not the timing chain slapping?

are you sure its not piston slap?

Or an exhaust leak?

do you have a collapsed/sticky lifter, or is the cam worn out?

is it full of sludge? pull the valve cover and have a look see.
while the cover is off, put a breaker bar on the crank and rotate it slowly left and right. can you turn the breakerbar a ways before the valve train starts moving? this would indicate a sloppy timing chain.

Just a few things to think about :)

If sludge, not mileage is your issue, some have reported satisfactory results with atf/engine flush but just think of where all that crap goes once it's dislodged.

usually once you pull an engine apart to fix one thing, it will keep leading you to other things until your sending the block in for machine work and a complete rebuild. I have noticed that my 4.0 seems to run quieter on certain brands of oil. and strangely enough gets louder with the use of 10w40 rather than the recommended 10w30. I like napa gold/wix filters.

the more info you can give us regarding your problem will help us in giving you a correct diagnosis.

IMO, as long as your timing chain is good: experiment with oil brands, buy a flowmaster, and turn your radio up. :D
 

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Discussion Starter · #3 ·
It seems to go away if i start it and drive sorta easy for a ways can the lifter be tightened (torqued to spec) she has 302k but its been pulled behind a camper alot so its not on the engine it runs like a top and its louder when u start then when your driving
 

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The rocker arms on the 2.5 are non adjustable. This means that unless the bolt has backed out (unlikely,) torqueing them will do nothing for you. you can try shimming them but they are hydraulic lifters so its really just a bandaid that will catch up to you eventually.

usually its best to replace the cam/lifters/as a set. they are pretty cheap. proper break in procedure is crucial to a reliable installation. I've heard mixed results with poeple who replaced just one lifter.

The best thing you can do for your engine is let it warm up for at least 5 mins. before you drive it.the reason it gets quieter is the metal parts expand as they heat taking up the tolerances. Cold engine parts= More clearance = more noise = accellerated engine wear.

You can try running a qt of atf or marvel mystery oil for a while and see what that does but its hit or miss whether it will actually do anything.
 

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You can try running a qt of atf or marvel mystery oil for a while and see what that does but its hit or miss whether it will actually do anything.
That may help, but only if the problem is gummy lifters. If the cam lobe is flat, which is what I suspect, it won't restore lost metal. WaWheeler is right; replace cam and lifters, and timing chain for best results. Let me know how it goes, I need to do it to my 4 banger as well.:)
 

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also a good idea to inspect your distributor gear. every once in a while you'll see a post where somebody has stripped one.. sloppy timing chains are hard on them. Its free and an easy enough job that theres no reason not to.
 
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