96 sport loose rocker arms - JeepForum.com

 
LinkBack Thread Tools
post #1 of 13 Old 01-17-2014, 11:19 PM Thread Starter
oldschool88
Registered User
1996 XJ Cherokee 
 
Join Date: Nov 2012
Location: cadillac
Posts: 41
96 sport loose rocker arms

The jeep has 100k on it , oil changed on time , last change was 10w 30 rotella t5 with mopar filter. The jeep had a knocking at idle that slowly went away. Now its back. So today I removed the valve cover and all but 4-5 rockers moved, when moving them by hand it produced a knock or tic. They aren't terribly loose, but i dont think they should be as loose as there are.I loosened all of them and retorqed them back down. It helped quite a bit with the knocking but its still there. Should I replace all the rocker arm bridges ? I think that could be my problem. Other then that I'm stumped.

oldschool88 is offline  
Sponsored Links
Advertisement
 
post #2 of 13 Old 01-17-2014, 11:21 PM Thread Starter
oldschool88
Registered User
1996 XJ Cherokee 
 
Join Date: Nov 2012
Location: cadillac
Posts: 41
The rockers are still loose after the being tightened, but not as loose as before.
oldschool88 is offline  
post #3 of 13 Old 01-18-2014, 01:48 PM Thread Starter
oldschool88
Registered User
1996 XJ Cherokee 
 
Join Date: Nov 2012
Location: cadillac
Posts: 41
No one ?
oldschool88 is offline  
post #4 of 13 Old 01-19-2014, 12:15 PM
AZ Jeff
Web Wheeler
2014 JK Wrangler 
 
Join Date: Sep 2005
Location: San Tan Valley Arizona
Posts: 7,698
Some rocker arms WILL be loose when the engine is off. When there is no oil pressure, the hydraulic valve lifters will leak down, and result in some valve lash when the valve is in the closed position.

The knocking at idle can be a valve train noise or piston slap. The valve noise is more metallic. A dowel rod or stethoscope will help isolate which is which. If they are minor, neither noise is an indication of a serious issue.

Rocker arm bridges or associated pieces normally only need replacment when they show signs of wear due to dirt in the oil or oil starvation. The amount of gunk in the rocker cover area can be an indicator of wear or starvation, but rocker removal and inspection is the best way.

AZ-Jeff
I don't own an XJ any longer, but I still think they are the best of all the Jeep products ever made. My XJ was my favorite vehicle in my 50+ years of driving.
So...I stick around and give advice.
AZ Jeff is offline  
post #5 of 13 Old 01-19-2014, 12:56 PM Thread Starter
oldschool88
Registered User
1996 XJ Cherokee 
 
Join Date: Nov 2012
Location: cadillac
Posts: 41
Alright , cool.. Good to know.. I really appreciate the help.
oldschool88 is offline  
post #6 of 13 Old 01-19-2014, 03:39 PM
CCKen
Web Wheeler
 
CCKen's Avatar
1999 XJ Cherokee 
 
Join Date: Jul 2011
Location: Canton
Posts: 3,435
After the engine has been sitting awhile and the lifters have bled down, there shouldn't be up & down (as in rock up & down) movement of the rocker (with the rocker set of the cylinder being checked at TDC compression stroke). This is zero lash. Side to side movement will be noticed, but shouldn't be real sloppy.

If there is noticeable up & down movement, remove the rocker set and inspect the wear between each rocker and its pivot. Excessive wear will cause up & down slop. If the wear is slight, the respective lifers may be worn or their cam lobes may be worn.

If only one rocker in a set exhibits excessive up & down movement, it may mean that lifter is worn and/or its cam lobe is worn.

Just a few things to be aware of....
CCKen is offline  
post #7 of 13 Old 01-19-2014, 06:47 PM
AZ Jeff
Web Wheeler
2014 JK Wrangler 
 
Join Date: Sep 2005
Location: San Tan Valley Arizona
Posts: 7,698
Ken, I disagree. I lifter that is completely bled down (due to age wear) can collapse enough to create slop (lash) in the valve train when the valve is fully closed.

I DO agree that inspection of the rockers is prudent if there is any doubt about engine oil cleanliness and supply to the valve train.

AZ-Jeff
I don't own an XJ any longer, but I still think they are the best of all the Jeep products ever made. My XJ was my favorite vehicle in my 50+ years of driving.
So...I stick around and give advice.
AZ Jeff is offline  
post #8 of 13 Old 01-19-2014, 07:35 PM
CCKen
Web Wheeler
 
CCKen's Avatar
1999 XJ Cherokee 
 
Join Date: Jul 2011
Location: Canton
Posts: 3,435
Quote:
Originally Posted by AZ Jeff View Post
Ken, I disagree.I lifter that is completely bled down (due to age wear) can collapse enough to create slop (lash) in the valve train when the valve is fully closed.

Agreed, if the lifter internal spring is shot it can be considered 'completely bled down', i.e, collaped. If the spring is still good and only the oil charge has bled down it may be still seviceable. What I was referring to was let the lifter bleed down to zero lash.

I DO agree that inspection of the rockers is prudent if there is any doubt about engine oil cleanliness and supply to the valve train.
The OP was looking into rocker movement issues.
CCKen is offline  
post #9 of 13 Old 01-20-2014, 09:00 AM
AZ Jeff
Web Wheeler
2014 JK Wrangler 
 
Join Date: Sep 2005
Location: San Tan Valley Arizona
Posts: 7,698
Quote:
Originally Posted by CCKen View Post
The OP was looking into rocker movement issues.
I understand and agree.

AZ-Jeff
I don't own an XJ any longer, but I still think they are the best of all the Jeep products ever made. My XJ was my favorite vehicle in my 50+ years of driving.
So...I stick around and give advice.
AZ Jeff is offline  
post #10 of 13 Old 01-21-2014, 08:34 AM
CCKen
Web Wheeler
 
CCKen's Avatar
1999 XJ Cherokee 
 
Join Date: Jul 2011
Location: Canton
Posts: 3,435
Quote:
Originally Posted by oldschool88 View Post
The jeep has 100k on it , oil changed on time , last change was 10w 30 rotella t5 with mopar filter. The jeep had a knocking at idle that slowly went away. Now its back. So today I removed the valve cover and all but 4-5 rockers moved, when moving them by hand it produced a knock or tic. They aren't terribly loose, but i dont think they should be as loose as there are.

Could you explain this a little more clearly.

I loosened all of them and retorqed them back down. It helped quite a bit with the knocking but its still there. Should I replace all the rocker arm bridges? I think that could be my problem. Other then that I'm stumped.
.
CCKen is offline  
post #11 of 13 Old 01-21-2014, 01:14 PM Thread Starter
oldschool88
Registered User
1996 XJ Cherokee 
 
Join Date: Nov 2012
Location: cadillac
Posts: 41
They had side to side movement, No up and down movement. It almost looks as if the rocker bridges are worn. Maybe ? It did seem to quiet the knocking I had before at idle.
oldschool88 is offline  
post #12 of 13 Old 01-21-2014, 02:03 PM
CCKen
Web Wheeler
 
CCKen's Avatar
1999 XJ Cherokee 
 
Join Date: Jul 2011
Location: Canton
Posts: 3,435
Quote:
Originally Posted by oldschool88 View Post
They had side to side movement, No up and down movement. It almost looks as if the rocker bridges are worn. Maybe ? It did seem to quiet the knocking I had before at idle.
It's easy to twist the bridges when loosening up the rocker bolts or when tightening them down.

If they are twisted they can be straightened out (if not dicked up too bad). If they can't be straightened buy new ones.

It might be a good idea to remove the rocker sets and see how worn the rockers and their respective pivots are. Rocker sets (rockers, pivots, and bridges) can be purchased. Elgin makes good sets.

When installing rockers, oil the bottom of the capscrews so they won't drag when tightening them down. Turn them down slowly, a bit at a time, until they bottom, then torque them to 21 foot pounds.

Last edited by CCKen; 01-21-2014 at 02:42 PM. Reason: foot pounds not inch pounds :-)
CCKen is offline  
post #13 of 13 Old 01-21-2014, 04:12 PM Thread Starter
oldschool88
Registered User
1996 XJ Cherokee 
 
Join Date: Nov 2012
Location: cadillac
Posts: 41
Okay , thanks for the info. I will be ordering new rockers and bridges soon. I will update this thread when I'm completed.
oldschool88 is offline  
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the JeepForum.com forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid e-mail address for yourself.



Email Address:
OR

Log-in









Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.




Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page



Posting Rules  
You may post new threads
You may 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 On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome