Rocker arms

Discussion in 'KJ General Discussion' started by Peter68, Nov 30, 2020.

  1. Peter68

    Peter68 New Member

    Messages:
    19
    Likes Received:
    1
    Joined:
    Oct 31, 2020
    Hey All, 2nd time liberty owner my first one was so good to me the new one not so much...A rocker fell off on the passenger side what is the recommended approach to take?
    Replace the one rocker arm and lifter?
    Replace all rocker arms and lifters since im in there ?
    i looked at amazon and mopar for parts but there is a wide range in pricing whats fan fav???


    Pete
     
  2. Chris French

    Chris French Member

    Messages:
    34
    Likes Received:
    8
    Joined:
    Oct 31, 2020
    Location:
    High Wycombe, UK
    I've been playing with rockers this weekend so let me share my experience and you can make your own mind up.

    Mines a 2004 3.7, but may be a later engine I'm not sure, can't find an engine number anywhere.

    I had a HGF and 3 (yup, amazed the engine wasn't destroyed!) rockers thrown off 3 different cylinders. It's all been apart and the heads went back on this weekend and I have been 'rubbing my chin' about what to do with the lash adjusters / lifters and rockers.

    I came across an interesting video on Utube, search on 'jeep rocker arm problems resolved with washers'. He proposes that the rockers are thrown because the lifter 'pocket' is sometimes milled too deep. So he puts in some washers to move the lifter up. Well, think what you want of that. The interesting thing for me is the criticality of the lifter position in its stroke and the proposal that mis-positioned, weak or stuck lifters can collapse when the engine is off, so when you turn over cold the rocker gets thrown? I took 2 lifters apart and the internals were stuck on both, that meant that with the engine off and no oil pressure the lifter drops by 2-3mm and everything becomes loose.

    I decided in the end to renew all the lifters as that is where I saw the problem, I kept the rockers. I test fitted them with washers underneath with the heads on the bench, but for my situation it looked like some valves were being held open and the lifters were at the very bottom of their stroke. So I decided just to go with new lifters, old rockers and see how it went.

    I am putting the exhaust back on tomorrow so I will let you know, but (IMO of course) this feels like the best solution for my engine. Replace lifters, keep rockers.

    I bought aftermarket unbranded rockers off ebay, £90 for 12 if that helps.

    Hope that all makes sense!
     
  3. tommudd

    tommudd Moderator Staff Member Moderator

    Messages:
    18,779
    Likes Received:
    773
    Joined:
    Jul 14, 2005
    Location:
    Southeastern Ohio
    Should replace both together
    like wearing one new sock and one worn out sock
    Good luck next time when you tear it down
     
  4. Peter68

    Peter68 New Member

    Messages:
    19
    Likes Received:
    1
    Joined:
    Oct 31, 2020
    I know sometimes aftermarket is bad for your ride would you say aftermarket rocker kit is fine in this case? its my daughter's car I dont expect my princess to be whellin... LOL!!!
     
  5. Peter68

    Peter68 New Member

    Messages:
    19
    Likes Received:
    1
    Joined:
    Oct 31, 2020
    Yeam man Thanks!!
     
  6. tommudd

    tommudd Moderator Staff Member Moderator

    Messages:
    18,779
    Likes Received:
    773
    Joined:
    Jul 14, 2005
    Location:
    Southeastern Ohio
    It does not matter if she is wheeling it or just driving down the road
    this sounds so familiar , like , oh so I don't use the brakes much so no reason to replace them,...

    Oh well we try
    carry on
     
  7. Chris French

    Chris French Member

    Messages:
    34
    Likes Received:
    8
    Joined:
    Oct 31, 2020
    Location:
    High Wycombe, UK
    I meant lifters!
     
  8. Chris French

    Chris French Member

    Messages:
    34
    Likes Received:
    8
    Joined:
    Oct 31, 2020
    Location:
    High Wycombe, UK
    I'm new to Jeep so you may well be right, we'll see over time. Replacing rockers isn't that big of a job, getting the covers off is the hard bit and its not that hard.

    I see it more like replacing your worn out socks and keeping your perfectly good shoes!
     
  9. tommudd

    tommudd Moderator Staff Member Moderator

    Messages:
    18,779
    Likes Received:
    773
    Joined:
    Jul 14, 2005
    Location:
    Southeastern Ohio
    :(
     
  10. Peter68

    Peter68 New Member

    Messages:
    19
    Likes Received:
    1
    Joined:
    Oct 31, 2020
    Thank you, everyone!! New lifters and rockers arms ordered via amazon!
    Trying to track down new valve cover bolts due to rusted bolts...
     
  11. Peter68

    Peter68 New Member

    Messages:
    19
    Likes Received:
    1
    Joined:
    Oct 31, 2020
    Now im at a loss...so amazon let me down by sending me wrong parts. Im in a pinch so I called local dealer they had a few rocker arms and a couple of lifters not enough to do the whole job. I grabbed 1 rocker arm and 1 lifter to fix what is known to be broken. No issues going back together...she runs fine on startup and then i get a P0306 code (misfire cylinder 6) i change the plugs with NGK Copper then i get a P303 code on startup. I figure its a bad coil pack because the trouble code moved to cylinder 3 and i shuffled the coil packs on reassembly on purpose, I grabbed 1 coil pack thinking its got to be a bad coil pack, I swapped the new one with every coil pack no change on any of them and it's still backfiring through the throttle body !!! I dont know what to do now...
     
  12. tommudd

    tommudd Moderator Staff Member Moderator

    Messages:
    18,779
    Likes Received:
    773
    Joined:
    Jul 14, 2005
    Location:
    Southeastern Ohio
    So local dealer did not have a full set ?
    I must be better supplied in my shop than a dealer then, have a full set liters, rockers etc all sitting on the shelf , waiting
     
  13. Peter68

    Peter68 New Member

    Messages:
    19
    Likes Received:
    1
    Joined:
    Oct 31, 2020
    Troiano Chrysler Jeep Colchester CT.......
     
  14. JeepJeepster

    JeepJeepster Full Access Member

    Messages:
    8,559
    Likes Received:
    68
    Joined:
    Dec 15, 2004
    Location:
    Dem hollers in Ky
    You swapped the new coil around and it always had a P303? How are you clearing the code?

    So started and idled good, gave a code, and now its backfiring through intake? Does it consistently backfire through the intake?
     
  15. Peter68

    Peter68 New Member

    Messages:
    19
    Likes Received:
    1
    Joined:
    Oct 31, 2020
    Yes.
     
  16. Peter68

    Peter68 New Member

    Messages:
    19
    Likes Received:
    1
    Joined:
    Oct 31, 2020
    I have a scan tools you connect thru your phone. I did not clear the code when I relocated known good coil pack each time ...should i have???
     
  17. tommudd

    tommudd Moderator Staff Member Moderator

    Messages:
    18,779
    Likes Received:
    773
    Joined:
    Jul 14, 2005
    Location:
    Southeastern Ohio
    remove both battery cables, connect them together
    go play jumping jacks for 30-45 minutes
    go back , hook cables up and see what it does, which if any codes

    By the way what year do you have ?

    some codes it takes a few starts and miles before they fully go away
     
  18. Peter68

    Peter68 New Member

    Messages:
    19
    Likes Received:
    1
    Joined:
    Oct 31, 2020
    2006
     
  19. Peter68

    Peter68 New Member

    Messages:
    19
    Likes Received:
    1
    Joined:
    Oct 31, 2020
    First thanks for you help Tommudd and Jeepster, I followed the instructions and it now has a code P0300 still backfiring ...
     
  20. JeepJeepster

    JeepJeepster Full Access Member

    Messages:
    8,559
    Likes Received:
    68
    Joined:
    Dec 15, 2004
    Location:
    Dem hollers in Ky
    I'm wondering if you have a valve stuck open...

    I would do a compression check.
     
    DadOSix likes this.