Non Valk Jeep 4.0 inline making clattering on startup.

[YoungPUP]

Long story short the wife's 03 Jeep with 135000 miles on it started making a clatter on startup about 6 months ago.  I narrowed it down to a sticking lifter.  Fed the motor the recommended amount of sea foam into the oil and it cleared right up.  Just did an oil change and now its doing it again.  Now I'm wondering if the sea foam was a patch or did it just mask the issue? The clatter isn't under the same circumstances now though. Before it was only after the truck had sat for a day or 2. Now it only does it after a short startup( ie. move it out of the garage then restart it to put it away)  I really don't want to tear this thing apart looking for clues. Thoughts  Ideas  Anything?    Thanks as always.

[Skinhead]

Long story short the wife's 03 Jeep with 135000 miles on it started making a clatter on startup about 6 months ago.  I narrowed it down to a sticking lifter.  Fed the motor the recommended amount of sea foam into the oil and it cleared right up.  Just did an oil change and now its doing it again.  Now I'm wondering if the sea foam was a patch or did it just mask the issue? The clatter isn't under the same circumstances now though. Before it was only after the truck had sat for a day or 2. Now it only does it after a short startup( ie. move it out of the garage then restart it to put it away)  I really don't want to tear this thing apart looking for clues. Thoughts  Ideas  Anything?    Thanks as always.

Did you use the same P/N , brand Oil Filter?  Some filters have a check valve that prevents the oil from draining out of the oil galleys when the engine is shut down.  If you used the same filter, the check valve may be defective.  For a quick and dirty check, I'd try another filter and see if it makes a difference.

[Gavin_Sons]

Try some marvel mystery oil. I have an 05 tundra double cab with 150000 miles and started replacing 1 quart of oil with 1 quart of mystery oil and it is quieter than it was brand new. Also dump a few ounces in the gas once a month.

[Momz]

One trick that may also work on an old style motor like your Jeep. is to drain about two quarts of oil, then add Auto trans fluid to the fill line. Drive at least 100 miles, then change your oil and filter.

Never had problems after that. Even did it on my 2004 Chevy truck with the 5.3 Vortec motor. Those Vortec 5.3's were notorious for lifter noise on start up. 

[sandy]

I'll bet your cam timing chain/gear are worn out. The chain is clattering around in the housing. My friend with an 89 recently changed his.

[The Anvil]

I'll bet your cam timing chain/gear are worn out. The chain is clattering around in the housing. My friend with an 89 recently changed his.

Certainly possible, but the fact that it cleared up for a time makes me think not. Timing gear/chain issues usualy just get worse and worse.

First of all, sticking lifters in the 4.0 make a definite "tick" not a clatter. Maybe our terminology is just different but sticking lifters on 4.0 and 2.5 inline Jeep motors are pretty much a given at that mileage. When they're just starting to go bad they tick on startup but quiet down once the engine warms up. After a while they'll do it all the time. I'd run it with the hood open and try and really narrow down the location of the sound, get a stethoscope if you have to. Take the oil cap off, does it get much louder? Could be a rocker or a broken spring. Coming from below down near the oil pan? You might be getting ready to spin a bearing which is a relatively easy fix if you get it before it sheds metal into the motor. Either way, cut that filter open and examine the element. That might tell you a lot.

[IamGCW]

One trick that may also work on an old style motor like your Jeep. is to drain about two quarts of oil, then add Auto trans fluid to the fill line. Drive at least 100 miles, then change your oil and filter.

Never had problems after that. Even did it on my 2004 Chevy truck with the 5.3 Vortec motor. Those Vortec 5.3's were notorious for lifter noise on start up. 

+1. 

[snohunter]

+1 on the filter change I work at a jeep dealer in the parts dept and own a 04 wrangler with a 4.0 had kinda the same thing happen to me .Short startup pulling out of garage after an oil change it would rattle like it was getting no oil for a few seconds new oil filter hasen't happened again . now mine only has 60,000 on it but sounds kinda the same to me

[YoungPUP]

Alright. Update, Kinda.  Changed the oil filter for another one of the same brand and flavor from a different store (Fram Ph16) Still doing it. From under the hood it seems to be loudest on the Right side of the motor near the distributor pickup. From in the seat it stop Immediately with the oil pressure gauge coming to life.  I pulled the distributor pickup sensor( it has coil on plug with a distributor-ish pickup)  I was able to grab the shaft end sticking out and atleast there is no wiggle there.  This weekend I'll pull the valve cover and look for wiggly push rods.  Yay!!!!   

[YoungPUP]

More update-ish. Had the valve cover off today. Broke the firkin oil dipstick off in the tube in the process.   No loose push rods. No broken springs or loose rockers.  Pulled the oil pan to get the broken dipstick and found a visibly drooping timing chain.  Atleast the positive is that its a 4.0 and not the 4.7 with 3 timing chains...

[The Anvil]

More update-ish. Had the valve cover off today. Broke the firkin oil dipstick off in the tube in the process.   No loose push rods. No broken springs or loose rockers.  Pulled the oil pan to get the broken dipstick and found a visibly drooping timing chain.  Atleast the positive is that its a 4.0 and not the 4.7 with 3 timing chains...

If it's visibly drooping it might be the tensioner.

[YoungPUP]

No tensioner, just a plastic block called a guide block to keep it from chewing on the cover.  Take off all the fuel injection and coil on plug and this is pretty much the same motor that Nash originally designed in the 50's.  That's a lot of why I bought this specific truck. The 4.0 inline 6 is barely above stone wheel simple.

[YoungPUP]

Final update. (yeah!!)  Changed out the timing chain on the Jeep yesterday. It was Definitely shot as I was able to pull it off of the gears without removing the gears.  Also stumbled across the cause of the mysterious coolant smell when I found a leaking tube in the radiator core.  Thanks for all the help!