i was doing an engine oil flush and this two small plastic fragments dropped out of the oil pan. i can't think of any parts of the engine use this kind of plastic. im hoping the previous owners dropped these inside the crank case by accident. can somebody please tell me what this is so i can stop sweating.

 

Hey! Dang good one! with no scale of reference, (like a Quarter), I might guess at least one is part of an old oil cap that broke off. The other longer one...Idk. Anyway...nothing to worry about..no piston...yet!

 

it's about the size of a pen head. thanks for the head up now that you mention about the oil cap cuz that's like about the same color only these are lighter color.

 

Yea, I recognized the color....I confess, my 4.0 might make 3ook..and when it goes I may, or may not autopsy it! OK I guessI will, probly will be a piston.

 

mine makes a ticking sound that's why i decide to do the motor flush and added one quart of lucas oil and it still does not quiet down. went to mech. shop and he said it's the wrist pin on the piston and nothing to worry about. is he right? btw it's a 2001

 

First, I'd call it an oil change, second I don't trust any one who has too much cash flow. Yea, probably all 7 wrist pins. Over 100K? Where do you live?. I mean, if you have some miles, put some 15-40 in it with a Wix filter, and concentrate on plugs, and sensors and basics.

 

7 wrist pins? You sure about that?

 

Ah! Getting it..slow junk...yes.the 4.0 is hardy and reliable. Over 100K? You didn't post it, but I bet you are not freezing. I run Castrol 30 wt, and nothing will fail...since it's not cold here. Don't use that oil to try to sharpen anything. Too slippery. No good for saws or drill bits. A wix filter (which Naps sells as there "premium"). You put those two together with the 4.0, and give it a minute to warm up when it's cold and it will outlast us! 15-40, is what some here run. I guess the idea is they made it so it changes thickness, thicker as it warms up. I haven't bothered to even check that. Good motor! .

In cold weather you need thinner oil.

 

Dang hamster, you got me. yea sometimes I run 9 but 6 seems to get me buy most days...just a slap at a shop...I trust no-one.... Also I have yet to hear if a wrist-pin problem on that goat. Not to say it can't happen, but seems a piston, or rod will go first, depending on what it's dealing with.

 

You likely are fine. Noise is normal. You might have an 0331 head though. # is on the drivers side top edge, of the head. IF you can find a "tupy" foundry mark, inside, under the oil cap that's good, (really good). If it's not a "revised" 0331 with the the tupy mark...be supper careful not to overheat it. (translated, if women or children are using it, put new hoses, at least). The head may well crack if some dummy thinks they will make it another 1/2 mile home. Really, an 0331 can crack.

 

sorry didn't give enough info. it's current at 156k miles, im the 6th owner and i live chicago. i have no history what been been to the jeep. i think maybe at one point the head been replaced before or i got lucky with is #0331 cuz i didn't see any sign of oil in coolant or low coolant. i recently flush out coolant, oil 10w30, mopar #090 filter, trans, and all those regular maintence. it's running good just the ticking noise. winter here in chicago can be real nasty so i don't think i want to put any high viloscity oil in the jeep cuz it might makes it real hard to start.

 

Some vehicles have plastic (teflon or nylon) coated timing sprockets that will break and leave junk like that in the pan. Not sure if the 4.0 came with those sprockets though.

 

would that be bad thing or can i get by since only small pieces broked off?

 

It could have been your lifter breather valve that just broke and the PO replaced it and some fell into the engine.

This little guy, mine busted into little bits when i tried to get it out.

 

this is lite brown color not black