Results 1 to 19 of 19

Thread: Burning oil and smoke

  1. #1
    Join Date
    Oct 2008
    Location
    Braselton
    Posts
    1,625

    Default Burning oil and smoke

    I burn about 1 qt. in 1000 miles, and smoke at high RPM. I ran a compression test and I got 180 psi in all four cylinders. I guess I can do a leak down test? But if the compression test came out good, does that narrow it down to where it's burning oil? The motor has 170k miles, it's a SNC, 1990 and I run Vavoline 20w50 syth blend to cope with the burning oil.

  2. #2
    Join Date
    Aug 2008
    Posts
    2,470

    Default

    is it too full? ands give valvoline hugh mileage s shot next time.
    '95 w/ now finished '99 swap, kyb agx's, flyin miata springs, sway bars, roll bar and more to come...

  3. #3
    Join Date
    Oct 2008
    Location
    Braselton
    Posts
    1,625

    Default

    Nope, it burns oil so it's usually low lol.

  4. #4
    Join Date
    Jul 2008
    Location
    City of Decatur
    Posts
    2,162

    Default

    Check the PCV valve. Mine will blow a huge smoke screen- but if I pop the hood and whack the PVC valve it stops. My compression numbers were similar, a little higher, but not much. I figure the PCV valve and old valve seals are my problem.
    | 90 Miata | Stock FE-dohc 2.0L engine swap | T3/T04e - Stage3/48AR - 50trim/60AR | Zero-mile-per-year member

  5. #5
    Join Date
    Sep 2008
    Location
    Tampa, FL
    Posts
    1,231

    Default

    Quote Originally Posted by FE3tMX5 View Post
    if I pop the hood and whack the PVC valve it stops

    LOL, ever thought about replacin that sum*****?
    2010 MX-5 PRHT - 1989 Mirage Turbo - www.facebook.com/doomwolfmetal <<< METAL!

  6. #6
    Join Date
    Jul 2008
    Location
    City of Decatur
    Posts
    2,162

    Default

    Yes. But only when I start the car up and it smokes. And at that point all I want to do is go. Sometimes I just burn a bunch of oil and it fixes itself when it warms up, or I hit a bump.
    | 90 Miata | Stock FE-dohc 2.0L engine swap | T3/T04e - Stage3/48AR - 50trim/60AR | Zero-mile-per-year member

  7. #7
    Join Date
    Aug 2008
    Posts
    2,470

    Default

    lawlz
    '95 w/ now finished '99 swap, kyb agx's, flyin miata springs, sway bars, roll bar and more to come...

  8. #8
    Join Date
    Apr 2009
    Location
    Decatur
    Posts
    5,784

    Default

    PCV is like $6 right? How much do you pay for the oil you burn?
    Red '91, MSM longblock/BEGI-FM hybrid turbo w/2871r/3"Enthuza/Hydra2.7/700cc/Ohlins/
    RacingBrake11"BBK/SS HDDD/Nakamae everything/KGWorks/Zoom/We're done!

  9. #9
    Join Date
    Jul 2008
    Posts
    7,390

    Default

    Quote Originally Posted by oldgrayfrog View Post
    PCV is like $6 right? How much do you pay for the oil you burn?
    Its probably Scottish math, you wont understand it.
    http://www.mx5atlanta.com/forums/image.php?type=sigpic&userid=13&dateline=123560545  3

  10. #10
    Join Date
    Oct 2008
    Location
    Braselton
    Posts
    1,625

    Default

    Brand new PCV valve. I'm hoping it's just valve seals, that will be a lot easier than cylinder rings lol.

  11. #11
    Join Date
    Jul 2008
    Location
    City of Decatur
    Posts
    2,162

    Default

    I honestly can't seeing being rings with a compression check that looks that good... unless the cylinders are full of oil. Seriously, the plugs don't have oil on them do they?

    My last 1.6 was making ~160psi across the board and didn't burn any oil. That was an X auto X engine that had about 130k total miles- and 50k of those were with a supercharger, so there had to be some ring wear on it.
    | 90 Miata | Stock FE-dohc 2.0L engine swap | T3/T04e - Stage3/48AR - 50trim/60AR | Zero-mile-per-year member

  12. #12
    Join Date
    Oct 2008
    Location
    Braselton
    Posts
    1,625

    Default

    Plugs are completely dry.

  13. #13
    Join Date
    Aug 2008
    Posts
    2,470

    Default

    valve guides then, find another good head or rebuld that one.
    '95 w/ now finished '99 swap, kyb agx's, flyin miata springs, sway bars, roll bar and more to come...

  14. #14
    Join Date
    Oct 2008
    Location
    Braselton
    Posts
    1,625

    Default

    How much would that cost?

  15. #15
    Join Date
    Jul 2008
    Posts
    7,390

    Default

    $100 for the head and whatever you spend working it.
    http://www.mx5atlanta.com/forums/image.php?type=sigpic&userid=13&dateline=123560545  3

  16. #16
    Join Date
    Oct 2008
    Location
    Braselton
    Posts
    1,625

    Default

    A head that wouldn't need work? otherwise I'd just fix mine.

  17. #17
    Join Date
    Jul 2008
    Posts
    7,390

    Default

    Quote Originally Posted by Emerica44n View Post
    A head that wouldn't need work? otherwise I'd just fix mine.
    Who's to say whether a USED head 'needs' work.
    Put it this way, a used head that didnt have the issues yours seems too.

    Having an extra saves on down time too.
    http://www.mx5atlanta.com/forums/image.php?type=sigpic&userid=13&dateline=123560545  3

  18. #18
    Join Date
    Jan 2009
    Location
    McDonough!!!
    Posts
    1,347

    Default

    a compression test just show you are getting a seal not maintaining it.Leakdown test
    then figure out the fix.
    -G-
    Then:1994 Montego Blue 356,xxx Miles
    Now:1996 Explorer" The Zombie Attack Evasion Vehicle #543"

  19. #19
    Join Date
    Jul 2008
    Location
    City of Decatur
    Posts
    2,162

    Default

    I think it's the valve seals. Guides leak oil if they're good or bad- that's what the valve seals are for. Like Greg said, a leakdown will let you know for sure if you have ring issues, but my guess is that your ring are fine given the comp numbers.
    | 90 Miata | Stock FE-dohc 2.0L engine swap | T3/T04e - Stage3/48AR - 50trim/60AR | Zero-mile-per-year member

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •