Valve Lifter Question 2001 Jeep

I have a 2001 Jeep Wrangler with the 4.0 engine. It has 56,000 miles. When starting the engine there is a loud rapid ticking noise that last until the engine warms. It only does this when starting a cold engine but not every time, maybe 3 or 4 times a week. It first started doing this a little after 30,000 miles and then it stopped and now it's doing it again but more frequent. If I end up replacing the valve lifters does anyone know of a good place to buy the hydraulic lifter removal tool? Is this tool really needed or could I get by without it? Also will I have to remove the A/C compressor? The book wasn't real clear on this part of it. It didn't say anything about removing the A/C during the head removal procedure but did say to recharge after assembly. I like to know what I'm getting into before I start. I appreciate any help.

Thanks, Dennis

Reply to
Dennis
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I can't comment from experience on the job of head removal, or the use of the lifter removal tool. But I would suggest you make certain you aren't really hearing piston slap. I noticed that problem more often starting in the mid 90's on the Jeep 4.0. Anyway, as bad as the 4.0 still is for lifter noise and worn cam bearings that cause low oil pressure, those things usually become more noticable when the engine is hot, not cold. Piston slap from worn skirts (plus they're manufacturered short to begin with) will cause a rattle type noise when cold that goes away hot. Piston slap isn't as much a mechanical problem as it is an annoying sound. It is probably the least dangerous internal engine clearance related problem you could have.

RE: A/C compressor... as I remember it (at least in the Cherokee) there is enough hose available to move the compressor out of the way. By all means, try to move the compressor without discharging the system if at all possible.

Toyota MDT in MO

Reply to
Comboverfish

I was wondering if the noise could be from something other than the lifters because it last 4 or 5 minutes. I'v always thought that lifter noise disappeared a few seconds after starting the engine. I'm not sure if I've ever heard piston slap before so I don't know how it would sound. We bought the jeep new and it has always been properly serviced.Could it be possible that the piston skirts could be worn so bad as to cause this noise with only 56,000 miles? If it is piston slap, wouldn't it make this noise every time the cold engine was started? Not being an expert is there a way to tell if the noise is coming from the pistons or the lifters? I don't want to install new lifters and still have the same problem, which is how my luck goes. Thanks for your response.

Dennis

Reply to
Dennis

You should post this over on rec.autos.makers.jeep+willys. I know there are some 'lifter noise' issues with a few different years of the 4.0's.

Most of it's harmless or only needs putting some cleaner through.

The 'usual' cause of a new 'knock' when cold is a cracked exhaust manifold. They make a very deceiving knock noise when they crack and it is common.

Mike

86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail >
Reply to
Mike Romain

Thanks Mike for your response.

Reply to
Dennis

You might try removing one wire at the time each morning when you 1st start the engine WHEN the ticking is occurring. Note whether the noise changes when you remove a certain wire. If so, chances are better that the noise comes from a piston than lifter, esp. if it stops and re-occurs when you remove-and-replace that wire. If you determine it's a lifter, it'd be wise to follow Mike R's advice and use a good lifter cleaner. May be merely a little varnish/'trash' that needs removing by the cleaner. s

Reply to
sdlomi2

To the first part- piston slap on ALL cylinders makes a gasoline engine sound almost exactly like a diesel. If its just on one cylinder, it sounds more like a knock, but not quite as deep.

Lifter "tick" sounds higher in pitch, and a lifter with a cranky check ball CAN continue to click much longer than just a few seconds after startup.

If I were you, I'd change oil filter brands to one with a good check valve (Wix, Purolator, never Fram). A filter that allows oil drain-back can really aggravate lifter tick, and can also explain why its worse some times than it is others.

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Reply to
Steve

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