1. Welcome to Jeeps.net!

    You are currently viewing as a guest! To get full-access, you need to register for a FREE account.

    As a registered member, you’ll be able to:
    • Participate in all Jeep discussion topics
    • Transfer over your build thread from a different forum to this one
    • Communicate privately with other Jeep owners from around the world
    • Post your own photos in our Members Gallery
    • Access all special features of the site

93 ZJ 5.2L Compression Test

Discussion in 'Grand Cherokee' started by TinyInkognegroT, Jun 25, 2019.

Page 1 of 3
  1. Jun 25, 2019 at 7:20 PM
    #1
    TinyInkognegroT

    #1
    TinyInkognegroT [OP] Well-Known Member

    Joined:
    May 26, 2019
    Member:
    #3261
    Messages:
    576
    Gender:
    Male
    Vehicle:
    1993 Grand Cherokee Limited 5.2L AWD
    Did a compression test today on all 8 cylinders with a compression kit some guy brought to do his engine in my complex... Here are the results

    received_699382393850069.jpg
     
    TinyInkognegroT, Jun 25, 2019
    #1
    JKBob 25 likes this.
  2. Jun 25, 2019 at 7:28 PM
    #2
    aggrex

    #2
    aggrex Well-Known Member

    Joined:
    Sep 12, 2016
    Member:
    #203
    Messages:
    4,912
    DE
    Vehicle:
    Backcountry '16
    Tuffy>AEV>TTO>JW>STech>EVOcage>MagnaFlow>SpiderTrax>RockHard>TF>SpringTail>67design>Bolt>GPCA>Curt>
    Cylinder #4 looks interesting.
     
    aggrex, Jun 25, 2019
    #2
    JKBob 25 and TinyInkognegroT[OP] like this.
  3. Jun 25, 2019 at 7:31 PM
    #3
    TinyInkognegroT

    #3
    TinyInkognegroT [OP] Well-Known Member

    Joined:
    May 26, 2019
    Member:
    #3261
    Messages:
    576
    Gender:
    Male
    Vehicle:
    1993 Grand Cherokee Limited 5.2L AWD
    Just cylinder 4 ?
     
    TinyInkognegroT, Jun 25, 2019
    #3
  4. Jun 25, 2019 at 7:31 PM
    #4
    TinyInkognegroT

    #4
    TinyInkognegroT [OP] Well-Known Member

    Joined:
    May 26, 2019
    Member:
    #3261
    Messages:
    576
    Gender:
    Male
    Vehicle:
    1993 Grand Cherokee Limited 5.2L AWD
    I don't even know the firing order or the wiring...
     
    TinyInkognegroT, Jun 25, 2019
    #4
  5. Jun 25, 2019 at 7:35 PM
    #5
    aggrex

    #5
    aggrex Well-Known Member

    Joined:
    Sep 12, 2016
    Member:
    #203
    Messages:
    4,912
    DE
    Vehicle:
    Backcountry '16
    Tuffy>AEV>TTO>JW>STech>EVOcage>MagnaFlow>SpiderTrax>RockHard>TF>SpringTail>67design>Bolt>GPCA>Curt>
    hqdefault.jpg
     
    aggrex, Jun 25, 2019
    #5
    JKBob 25 and TinyInkognegroT[OP] like this.
  6. Jun 25, 2019 at 7:46 PM
    #6
    TinyInkognegroT

    #6
    TinyInkognegroT [OP] Well-Known Member

    Joined:
    May 26, 2019
    Member:
    #3261
    Messages:
    576
    Gender:
    Male
    Vehicle:
    1993 Grand Cherokee Limited 5.2L AWD
    Yes cylinder 4 is interesting. These results were after 7 turnovers each. What is the right pressure for these cylinders ?
     
    TinyInkognegroT, Jun 25, 2019
    #6
  7. Jun 25, 2019 at 8:29 PM
    #7
    aggrex

    #7
    aggrex Well-Known Member

    Joined:
    Sep 12, 2016
    Member:
    #203
    Messages:
    4,912
    DE
    Vehicle:
    Backcountry '16
    Tuffy>AEV>TTO>JW>STech>EVOcage>MagnaFlow>SpiderTrax>RockHard>TF>SpringTail>67design>Bolt>GPCA>Curt>
    For the age of the motor I think the psi are on target....except the one
     
    aggrex, Jun 25, 2019
    #7
    JKBob 25 and TinyInkognegroT[OP] like this.
  8. Jun 25, 2019 at 8:49 PM
    #8
    TinyInkognegroT

    #8
    TinyInkognegroT [OP] Well-Known Member

    Joined:
    May 26, 2019
    Member:
    #3261
    Messages:
    576
    Gender:
    Male
    Vehicle:
    1993 Grand Cherokee Limited 5.2L AWD
    What are some causes of this ?
     
    TinyInkognegroT, Jun 25, 2019
    #8
  9. Jun 26, 2019 at 3:54 AM
    #9
    aggrex

    #9
    aggrex Well-Known Member

    Joined:
    Sep 12, 2016
    Member:
    #203
    Messages:
    4,912
    DE
    Vehicle:
    Backcountry '16
    Tuffy>AEV>TTO>JW>STech>EVOcage>MagnaFlow>SpiderTrax>RockHard>TF>SpringTail>67design>Bolt>GPCA>Curt>
    The causes can vary: been that way, high mileage, negligence, etc.
     
    aggrex, Jun 26, 2019
    #9
    JKBob 25 and TinyInkognegroT[OP] like this.
  10. Jun 26, 2019 at 6:17 AM
    #10
    TinyInkognegroT

    #10
    TinyInkognegroT [OP] Well-Known Member

    Joined:
    May 26, 2019
    Member:
    #3261
    Messages:
    576
    Gender:
    Male
    Vehicle:
    1993 Grand Cherokee Limited 5.2L AWD
    Is it something I should worry about ? How can I fix it ?
     
    TinyInkognegroT, Jun 26, 2019
    #10
  11. Jun 26, 2019 at 6:22 AM
    #11
    Awrench

    #11
    Awrench Well-Known Member

    Joined:
    May 12, 2018
    Member:
    #2303
    Messages:
    975
    Gender:
    Male
    Vehicle:
    3 jeeps
    IDEALLY a compression leak down - yeah I am spoiled with a shop and all the gizmos.
    With #4 on compression - both valves closed - compressed air (shop air) is fed into cylinder thru plug hole - listening to where air leaks out (intake, exhaust, crankcase) helps locate the issue.

    just #4 being low, Is there any evidence of water/coolant in oil?
    > I would do a wet compression test - adding @ a teaspoon of oil thru spark plug hole and retry readings.
    >Confirm both valves are closing, removing valve cover to inspect.
    > You may try adding some combustion chamber cleaner ito plug hole, this would frree a sticking piston ring - then retesting.
     
    Awrench, Jun 26, 2019
    #11
    JKBob 25, TinyInkognegroT[OP] and aggrex like this.
  12. Jun 26, 2019 at 6:35 AM
    #12
    TinyInkognegroT

    #12
    TinyInkognegroT [OP] Well-Known Member

    Joined:
    May 26, 2019
    Member:
    #3261
    Messages:
    576
    Gender:
    Male
    Vehicle:
    1993 Grand Cherokee Limited 5.2L AWD
    My grandpa has a shop but he's almost 40 miles away lol and no water or coolant in the oil. Best I can do as soon as possible is the combustion chamber then go on from there. I have a job interview today, so hopefully I get this job and bring in some tool and repair money
     
    TinyInkognegroT, Jun 26, 2019
    #12
    JKBob 25 likes this.
  13. Jun 26, 2019 at 6:36 AM
    #13
    TinyInkognegroT

    #13
    TinyInkognegroT [OP] Well-Known Member

    Joined:
    May 26, 2019
    Member:
    #3261
    Messages:
    576
    Gender:
    Male
    Vehicle:
    1993 Grand Cherokee Limited 5.2L AWD
    Could it be the cause of my "surge" problem I posted earlier ?
     
    TinyInkognegroT, Jun 26, 2019
    #13
  14. Jun 26, 2019 at 7:21 AM
    #14
    Awrench

    #14
    Awrench Well-Known Member

    Joined:
    May 12, 2018
    Member:
    #2303
    Messages:
    975
    Gender:
    Male
    Vehicle:
    3 jeeps
    good luck today.

    I do not see a surge issue, was it in another post topic?
    Anyway post a NEW topic with any other issues -
     
    Awrench, Jun 26, 2019
    #14
    JKBob 25 and TinyInkognegroT[OP] like this.
  15. Jun 26, 2019 at 8:00 AM
    #15
    TinyInkognegroT

    #15
    TinyInkognegroT [OP] Well-Known Member

    Joined:
    May 26, 2019
    Member:
    #3261
    Messages:
    576
    Gender:
    Male
    Vehicle:
    1993 Grand Cherokee Limited 5.2L AWD
    Thank u ! Yea its another topic I posted
     
    TinyInkognegroT, Jun 26, 2019
    #15
  16. Jun 26, 2019 at 11:11 AM
    #16
    TinyInkognegroT

    #16
    TinyInkognegroT [OP] Well-Known Member

    Joined:
    May 26, 2019
    Member:
    #3261
    Messages:
    576
    Gender:
    Male
    Vehicle:
    1993 Grand Cherokee Limited 5.2L AWD
    On this diagram, is coil in the middle of the cap ? From #1 on the cap, does it go by number order or by firing order ?
     
    TinyInkognegroT, Jun 26, 2019
    #16
  17. Jun 27, 2019 at 5:46 PM
    #17
    TinyInkognegroT

    #17
    TinyInkognegroT [OP] Well-Known Member

    Joined:
    May 26, 2019
    Member:
    #3261
    Messages:
    576
    Gender:
    Male
    Vehicle:
    1993 Grand Cherokee Limited 5.2L AWD
    Read online the best combustion chamber cleaner is distilled water from a spray bottle...in case chamber 4 is sticking
     
    TinyInkognegroT, Jun 27, 2019
    #17
  18. Jun 27, 2019 at 5:49 PM
    #18
    TinyInkognegroT

    #18
    TinyInkognegroT [OP] Well-Known Member

    Joined:
    May 26, 2019
    Member:
    #3261
    Messages:
    576
    Gender:
    Male
    Vehicle:
    1993 Grand Cherokee Limited 5.2L AWD
    Screenshot_20190627-194852.jpg
     
    TinyInkognegroT, Jun 27, 2019
    #18
  19. Jun 28, 2019 at 6:34 AM
    #19
    aggrex

    #19
    aggrex Well-Known Member

    Joined:
    Sep 12, 2016
    Member:
    #203
    Messages:
    4,912
    DE
    Vehicle:
    Backcountry '16
    Tuffy>AEV>TTO>JW>STech>EVOcage>MagnaFlow>SpiderTrax>RockHard>TF>SpringTail>67design>Bolt>GPCA>Curt>
    I'm not convinced this is effective and if done improperly connecting rods can hurt your ankles.
     
    aggrex, Jun 28, 2019
    #19
  20. Jun 28, 2019 at 6:39 AM
    #20
    TinyInkognegroT

    #20
    TinyInkognegroT [OP] Well-Known Member

    Joined:
    May 26, 2019
    Member:
    #3261
    Messages:
    576
    Gender:
    Male
    Vehicle:
    1993 Grand Cherokee Limited 5.2L AWD
    What do you mean by this ?
     
    TinyInkognegroT, Jun 28, 2019
    #20
Page 1 of 3
Register FREE to Reply!
To Top