Topic: Rattling noise when cold.

[sharpxmen]

Actually the piston Slap was listed for a tj when I did find it..  I was just showing the above as a way to check for piston slap.

for the 2.5L 91 and up they had some issues with the tolerances in the block, the fix was to install slightly oversized pistons (at the stealership under warranty) based on the bore, the pistons on these can't be knurled, the alloy they are made of is harder. There were also some engines that came out of the factory with o/s pistons and also o/s main and rod bearings (issues with the crank machining). I read it somewhere in the FSM, but that's when they're almost new, when there's lots of miles on them the issue is probably different and not factory machining errors.

[shovelhead]

I had a weak fuel pump for about a year, ever since I bought the Jeep.  I posted about it in another thread. Who knows how long it was weak before I got it.  I wonder if there is a carbon build up issue, due to the prolonged period of a weak fuel pump.  Perhaps the fact that the Jeep was unable to be run hard enough to clear out some of the carbon once in a while led to that rattle.  Friday afternoon I was able to really step on it, driving on the freeway, up a steep incline.  I'm hoping that it doesn't come back, and was just a carbon buildup issue.

[shovelhead]

The rattle noise is back.  It seems like there's two distinctive sounds being generated.  I think that I might have two separate issues.  One sounds like its in the top end, perhaps a rocker or lifer issue.  The other is more pronounced when it's cold.  I took the belt off this afternoon and briefly ran the engine and used a hard wood stick, and held it to different parts of the engine.  One of the loudest areas was on the timing chain cover.  I could actually feel the knock there in time with the sound.  I pulled off the dizzy cap, and used a wrench on the harmonic balancer to see how much play there was in the chain.  There's a bit of play between turning the balancer and when the rotor on the dizzy turns.  Perhaps I have some timing chain noise along with lifter noise?  I made two more videos as well.

http://youtu.be/kVC4SWDOVqY

and

http://youtu.be/6ukm_Bi3zJE

[shovelhead]

Broken piston skirt, cylinder #3.

http://assets6.pinimg.com/upload/137641332332254126_J7h51Z6A.jpg

http://media-cache-ec0.pinterest.com/upload/137641332332254125_0bW3MH7N.jpg

[shovelhead]

Does anyone know of a reputable and reasonable automotive machine shop in southern California?

[Tr00b]

Dang dude. That sucks. Might be easier to just get a fresher engine and drop that in. I don't know about in CA but a decent used 4cyl is only bringing around $3-500. Unfortunately that is the best idea I have.

Mine also makes a similar noise, but not as bad. It lasts about 30 sec after startup and only does it occasionally. Did you notice the engine ran rougher or had more vibration when it ran?

[grumpygy]

HAve not used this place in years But Smokies Cervice Center on Hill Street in OceanSide Calif.  Searching they still seem to be open.


  And just have to say would not Piston Slap cause that.

[shovelhead]

I've had that rattle issue for close to a year.  It just started getting much worse in the last few days.  It might have been piston slap before, which  progressed into piston failure.  I didn't notice any loss in power, but I did have quite a bit of blowby coming out of the valve cover.  There might have been more vibrations, it's difficult know know, because I recently replaced the motor mounts with Brown Dog polyurethane mounts, and you feel everything with those.

[shovelhead]

What is the likelihood that I could get away with putting four new pistons and piston rings in?  Would this require a rebuild?

[Jeffy]

If the cylinder walls look good then it wouldn't be a problem.

[shovelhead]

Rather than do the piston and ring job, I decided to go for a rebuild.  I used a local shop in Anaheim, CA.  They picked up my engine from my house, and dropped it off when they were done.  It took about a day to get the engine installed.  Started her up, ran through the initial break in, and she purrs like a kitten now.

[Jeffy]

That's cool, a door-to-door service.

[AWK]

Your sound was a lot like mine in my 97.   My son fixed it in July by throwing the #3 rod out the side of the block.   Mine would get quieter when warm.  I also got rid of some of the noise by going to a High Mileage semi synthetic oil.   Good luck with it.  Post it when you find the issue.

AWK

[sharpxmen]

Your sound was a lot like mine in my 97.   My son fixed it in July by throwing the #3 rod out the side of the block.   Mine would get quieter when warm.  I also got rid of some of the noise by going to a High Mileage semi synthetic oil.   Good luck with it.  Post it when you find the issue.

AWK

he found the issue, broken piston skirt and he replaced the motor (you missed the last  couple of posts)