2.5L Engine Rattle? - Jeep Wrangler Forum
Jeep Wrangler Forum

Go Back   Jeep Wrangler Forum > TJ Jeep Wrangler Forum > TJ General Discussion Forum

Join Wrangler Forum Today


Reply
 
Thread Tools

Please support our sponsors and let them know you heard about them on WranglerForum.com
Old 09-18-2007, 03:04 PM   #1
Newb
 
Join Date: Sep 2007
Posts: 4
2.5L Engine Rattle?

I have a 99 TJ with the 2.5 @ 98,000 miles. My problem is the motor rattles like no tomorrow. The sound is definetly coming from the valve cover. Just want to know if this is a common issue with this motor and what the fix is. I am not an inexperienced mechanic. Have been a garage wrench for a lot of years, I just want a little heads up before I go tearing the valve cover off and I am confronted with something I have never seen before.
Thanks in advance for your help.
Jim

99TJSofttop is offline   Quote
Old 09-18-2007, 04:11 PM   #2
Jeeper
 
whiteyj's Avatar
 
Join Date: Jul 2005
Location: Pleasanton CA
Posts: 4,859
One man's rattle.....

Not to be a smart ass but are you sure it's a rattle?

I just played this game for three visits with our Saturn.
There was a rattle coming from the right front strut tower.
The Saturn "technicians" were unable to locate a rattle.
On the third attempt I started making a stink and all of a
sudden the rattle was infact a "suspension knock".

JA's with comuters do not equal mechanics!

Sure it's the valve cover area and not CAT?

__________________
Fallen Angel...Former MOD
whiteyj is offline   Quote
Old 09-18-2007, 05:28 PM   #3
Jeeper
 
Boulderv7's Avatar
 
Join Date: Nov 2006
Location: Grand Rapids MI
Posts: 127
does it sound like it might be spark knock? My little 4 banger had quite a problem with carbon buildup.....some seafoam and it cleaned it right up.
__________________
Boulderv7

.....01 TJ 4 banger, 2 in lift, 32x11.5 on 15x10 black steelies.....
Boulderv7 is offline   Quote
Old 09-19-2007, 08:51 AM   #4
Newb
 
Join Date: Sep 2007
Posts: 4
Absolutely sure the sound is coming from the valve cover. It is for sure not a suspension issue. This is a rattle from the valve cover, sounds to me it could almost be a collapsed lifter. Just looking for someone here who might have some experience with the 2.5 that could point me in the right direction.

For the record, I have worked on vehicles in one capacity or another for 17 years. Started out working in a muffler and brake shop, got my certs and then began working in dyno labs on prototype engine testing. Like I said I have just never had one of these engines apart and would like a heads up before I start tearing this thing apart since it is my daily driver and I can't afford to have it down for an extended period of time.
99TJSofttop is offline   Quote
Old 09-19-2007, 10:12 AM   #5
Jeeper
 
Join Date: Sep 2007
Posts: 61
Well its hard to determine the sound of a knock like that withought hearing it.

Just a theory.
But my 95 Cherokee had what I've head refferd to many times as Piston Slap.
Basicaly there is enough materal worn off the cyclinder and piston skirts its clicking aginst the cyclinder wall on the power stroke. Almost sounds like a quiet desiel. And because it always happens at the top of the poser stode it sounds like its happening in the head.



But also compleatly quite possible you have a lifter that went flat, but if that happened it would be running horribly rough.

I would lean more towards either the first thing, or you have have excessive valve wear and the rockers need adjusted back to spec. If its running fine otherwise.

Nothing special with these engines, basicaly half a pushrod v-8, other than it is a PITA to remove the lifters.
blktrax is offline   Quote
Old 09-19-2007, 11:30 AM   #6
Newb
 
Join Date: Sep 2007
Posts: 4
Blktrax, do you know if the rockers are adjustable? I had heard they were a pedestal mount rocker and therefore non-adjustable. If they are I may just get a valve cover gasket and give the adjustment a try.
99TJSofttop is offline   Quote
Old 09-19-2007, 12:18 PM   #7
Jeeper
 
Join Date: Sep 2007
Posts: 61
Yes they are pedistal mount, sorry about the adjust part, had my hand in too many honda engines.

Other than valve cover gaskets and timing cover gaskets, I've never had to mess with a valve train in a 4.0 or 2.5 even with 200K miles, thew in a head gasket decked the block and head smammed it back together.


An intresting read. and some good illustrations

http://www.angelfire.com/my/fan/roller_rockers.html

The pain about the lifters in these engines is the heads have to come off to remove them. see the third part of that how to.
blktrax is offline   Quote
Old 09-19-2007, 01:10 PM   #8
Newb
 
Join Date: Sep 2007
Posts: 4
Thanks a bunch for the help.
99TJSofttop is offline   Quote
Old 09-19-2007, 01:27 PM   #9
Jeeper
 
Join Date: Sep 2007
Posts: 61
no problem
blktrax is offline   Quote
Old 08-13-2011, 10:10 AM   #10
Newb
 
Join Date: Aug 2011
Posts: 2
i have the same problem with my '99 jeep wrangler and i tore the valve cover off and replaced the lifters and the push rods and rocker arms but found out that it is much deeper than that it is some where in the lower end of the engine
jeeplover83 is offline   Quote
Old 08-13-2011, 10:14 AM   #11
Newb
 
Join Date: Aug 2011
Posts: 2
Quote:
Originally Posted by blktrax View Post
Yes they are pedistal mount, sorry about the adjust part, had my hand in too many honda engines.

Other than valve cover gaskets and timing cover gaskets, I've never had to mess with a valve train in a 4.0 or 2.5 even with 200K miles, thew in a head gasket decked the block and head smammed it back together.


An intresting read. and some good illustrations

Yella Terra Roller Rocker Installation Jeep 4.0L Engine

The pain about the lifters in these engines is the heads have to come off to remove them. see the third part of that how to.
i would have to agree i spent almost three hours trying to replace the lifters if you have any questions just ask i will try to respond to your post as soon as posible

jeeplover83 is offline   Quote
Reply

Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
rebuilding your engine?? Get Stroked!!! jeeper95yj YJ General Discussion Forum 6 01-01-2014 05:47 PM
more juice 95_YJ YJ Tech Forum 8 09-08-2009 01:52 PM
1989 2.5l Engine lholley33 YJ Tech Forum 6 07-11-2008 03:10 PM
2.5L to 4.0L Engine Swap DustyJeep YJ Tech Forum 2 01-09-2007 05:44 PM
95 YJ 2.5L 4 cylinder, engine knocking cowboy724 YJ General Discussion Forum 6 03-12-2006 10:42 PM



Download our Mobile App

» Network Links
»Jeep Parts
» Featured Product

All times are GMT -5. The time now is 10:48 PM.



Jeep®, Wrangler, Liberty, Wagoneer, Cherokee, and Grand Cherokee are copyrighted and trademarked to Chrysler Motors LLC.
Wranglerforum.com is not in any way associated with the Chrysler Motors LLC