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Unread 07-01-2010, 05:47 AM   #31
Knuckelhead
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Quote:
Originally Posted by halo26 View Post
Hey knuckelhead,
On the last oil change it actually looked really good! It was the first change after I bought it (always nerve racking ), and I was surprised how good it was. I didn't open up the filter though... I will on this next change, this weekend (fingers crossed).

Thanks for the help!

-Halo
Post back as to what you find? Good luck!...

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Unread 07-01-2010, 07:39 AM   #32
Wheelin98TJ
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Take Nonya's advice with a grain of salt.

He is off his meds or something.
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Unread 07-01-2010, 05:03 PM   #33
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Originally Posted by Wheelin98TJ View Post
Take Nonya's advice with a grain of salt.

He is off his meds or something.
Thanx for noticing that...
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Unread 07-01-2010, 05:28 PM   #34
SpaceWrangler
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He was at it a couple weeks ago also, ridiculing anyone who didn't agree with his viewpoints on cooling systems.

The guy's a loon.
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Last edited by SpaceWrangler; 07-01-2010 at 05:40 PM..
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Unread 07-01-2010, 05:49 PM   #35
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Originally Posted by Wheelin98TJ View Post
Take Nonya's advice with a grain of salt.

He is off his meds or something.
My thoughts exactly I was ribbing him a little over the weekend and he must have complained up a storm to one of the other mods on here and I got a nasty little PM from said mod stating to stop or else.... So I shall not direct another comment to him for fear of being banned...
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Unread 07-01-2010, 06:18 PM   #36
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Originally Posted by DevilDogDoc View Post
My thoughts exactly I was ribbing him a little over the weekend and he must have complained up a storm to one of the other mods on here and I got a nasty little PM from said mod stating to stop or else.... So I shall not direct another comment to him for fear of being banned...
Back up a couple pages and you'll see Nonya's been banned. Good riddance, I say. Slinging insults and belittling people are okay in the General Forums, but not in Tech.
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Unread 07-01-2010, 06:22 PM   #37
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Thanks for that bit of good news there stretch! Can't say I'm surprised, still a little miffed over that undeserved pm however I'll get over that I suppose...
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Unread 08-19-2010, 09:19 AM   #38
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Originally Posted by Dryseals View Post
You can continue to drive for a long time on a bad rod bearing if needed.
Sorry, but telling someone that it's OK to drive an engine with a suspected bad rod bearing is not good advice. A bad rod bearing will:

1) wear and cause low oil pressure
2) spin and trash the crank and possibly
3) lock up, bend or break the connecting rod and destroy the engine.
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Unread 08-19-2010, 11:01 AM   #39
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Originally Posted by scottbr View Post
Sorry, but telling someone that it's OK to drive an engine with a suspected bad rod bearing is not good advice. A bad rod bearing will:

1) wear and cause low oil pressure
2) spin and trash the crank and possibly
3) lock up, bend or break the connecting rod and destroy the engine.
Maybe, but if you look i said "if needed". Or in other words a person without the funds may just have too. I driven many cars with bad bearing for a long time and never had a problem. I've even watched friends purposely drive the #$#@ out of a motor to try and wreck it and the motor just keeps going.

The things you say are true, but a rod bad bearing is not a crucial as one might think and it can be run without repair.

We do a lot of vibration studies on very large industrial equipment, reciprocating compressors have run for months with bad rod bearing. More cost effective to continue to produce product. When the vibrations reach a certian level, we know we have a limited amount of time before the the rod goes. And that has a lot to do with where the rod is on the crank during the vibration.
For a four cycle motor, think about where the main pressure is on the rod during the different stoke positions. Your weak link is the rod bolts or the lower cradle of the bearing.
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Unread 06-06-2011, 12:44 PM   #40
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Check this out!

I have the same exact deal going on...2002 tj 4.0...Go to any auto parts store, and get a camshaft syncronizer. (besides advance, autozone, or orielys-they dont have it) the gears on this wear out, and start to slap off the gear on the camshaft. dont believe me? do what i did: tear the motor out from under the hood, divorce the timing chain from the motor, and turn your camshaft. i get to buy the upper and lower grind gasket sets now because i jumped the gun. I could have bought the cam syncro for 45 dollars...and be jeepin' around on this pure sunshine, 90 degree day. instead, im waiting for rtv to settle, and time to throw the motor back in. and hey, if it doesnt work, get your money back. i had one guy tell me to do the cam syncro...I SHOULD HAVE LISTENED. i joined jeepforum just to tell you this.
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Unread 04-27-2012, 11:41 PM   #41
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Quote:
Originally Posted by halo26 View Post
Hey Guys,
Long time reader/fan, first time poster...

A little background on my jeep... its a 2000 TJ Sport with the 4.0 and 'supposedly' is about to join the 200k club. I say supposedly because it runs like a champ, has 0 rust, and (from looking at the CarFax) the first owner put 120k on it in 1 year (we have a few theories, some more plausible than others).

Anywho...
My 4.0 just started making a noise I'm pretty sure is a broken piston skirt. I have no loss of power, etc... just the typical knocking (loud when cold, then much softer when warmed up).
My question is, (after I make certain it is a piston skirt) should I tare down the engine and replace the piston (hoping there's no damage done to the wall) or should I just keep wheeling it until I have an issue (more than just a noise) then replace the whole engine?


I'm very much a newbie, so if this has been hashed 100x or is common sense, please forgive my ignorance!

Any help would be GREATLY appreciated!

Thanks for reading!
Well what was the end result?

I had the same issue. When cold it would knock for awhile I thought it was top end. It started 2 years ago when it was REALLY cold, noise went away when tempurture was above freezing. Then then this winter came back except it knocked when it wasnt below freezing. I would ***** foot it untill it warmed up because of the noise but after 2 minutes it would go away. Well the other day the noise started half way too work when warm and didnt go away. I dropped the pan and planned on replacing the rod bearings except I found cylinder 3 piston broken, below ring. Tonight I pulled the head off and the cylinder looks ok. I guess tommorow Ill inspect the crank. I started a stroker build I got a 4.2 crank and rod.... well havent really started cause thats all Ive done. I really want to drive jeep this summer and if I start the stroker build it will take awhile. should I slap in a new piston if cylinder is not too out of round, and the crank isnt scored and wait for winter when I take it off the road, to start the stroker build. or do you think all the bearings are pooched and Im waisting my time?
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