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bad compression

Discussion in 'General Tech and Maintenance' started by FLounder, Jan 26, 2009.

  1. FLounder

    FLounder power hungry VIP

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    ran a compression test after doing a valve adjustment the other day. my engine is only 9.6:1 since its still the stock b20z block, but anyway its not good.... 190-165-145-200.

    cant figure out what the problem is. oil and coolant both look ok. not smoking except a slight amount at high rpms. no soot on the bumper or even the tailpipe. plugs look fine. might be time to rebuild. or any chance it could be just the head gasket?
     
  2. TurboMirage

    TurboMirage YEEAAAHHH VIP

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    try adjusting those valves again?

    may be a previous issue.
     
  3. austin20110

    austin20110 New Member

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    I dont have tooooo much experience with blown headgaskets but it doesnt seem thats what the problem is here... dont freak out yet
     
  4. eg6sir

    eg6sir Supa Mod Moderator VIP

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    bad rings most likely
     
  5. FLounder

    FLounder power hungry VIP

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    i did go back and check the valves again. they are spot on. i am a boat mechanic and i have adjusted a few valves before :D many 4 stroke outboards valves are similar to a b series honda. but yeah it could be rings i suppose.... im bummed
     
  6. TurboMirage

    TurboMirage YEEAAAHHH VIP

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    do a leak down test.
     
  7. Magana559

    Magana559 The Warden

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    try adding some oil in the cylinders......not much but a lil.

    try checking your compression before and then add the oil and check again.

    if your compression rises after the oil then you have a ring issue if not......... then is somewere else.
     
  8. GlassHeadlights

    GlassHeadlights West West Yall

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    There is still a posibility that you tightened them down too tight, you could loosen them up so they're tapping and try that.

    Tapping valves are better than valves that are too tight.


    I'm also assuming you warmed it up before the test.


    +1 on the leak down test.
     
  9. stuntstere

    stuntstere Member

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    Could possibly be a head gasket. If you look at the readings the 2 low cylinders are right next to each other. Only real way to find out is to leak down test it and figure out where your air escapes from.
     
  10. austin20110

    austin20110 New Member

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    good job on collecting what everyone else said and making it into one post
     
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